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What Are the Most Common Astaxanthin Side Effects?

By Henry Gaudet
Updated Jun 04, 2024
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The most commonly reported astaxanthin side effects are harmless pigment changes, such as a slightly orange tint to the skin or to stool. Even at high doses, no toxic effects have been observed, either in animals or humans. Other, less common astaxanthin side effects have a greater impact, and side effects such as low blood pressure and shifts in hormone levels can have serious health implications.

Astaxanthin is most commonly used as an additive to animal feed, and it adds pigment to crabs, shrimp, lobsters and salmon, giving them their familiar reddish orange color. As an animal feed supplement, astaxanthin is generally recognized as safe, according to the United States Code of Federal Regulations, and most people are able to consume astaxanthin-fed seafood without any reaction at all. In 1999, the U.S. Food and Drug Administration cleared astaxanthin as a food ingredient for human consumption.

As a dietary supplement, astaxanthin is most often used as an antioxidant to reduce cholesterol. Advocates also recommend astaxanthin to improve eye health and treat carpal tunnel syndrome, arthritis, muscle injury, gastrointestinal complaints and male infertility. It should be noted, however, that there is insufficient evidence to support any of these claims, and there is no proven health benefit to this supplement.

Common astaxanthin side effects include increased pigmentation, hair growth, shifts in hormone levels and low blood pressure. Reduced calcium levels, decreased libido and breast enlargement in men have also been observed, but these astaxanthin side effects are rarer. Allergic reactions also are possible and can be quite dangerous. Astaxanthin and astaxanthin-fed foods should be avoided by anyone with a known allergy to the substance.

Drug interactions are another serious concern. For instance, blood pressure medication might be amplified by astaxanthin and can cause blood pressure to dip dangerously low. Hormone treatments and birth control can be affected by the supplement’s effects on hormone levels. Similar cross-reactions have been observed with some antihistamines, and asthma medications might not react well to astaxanthin. Liver enzymes, which are responsible for removing a variety of drugs from the blood, also can be affected, resulting in increased levels of these drugs remaining in circulation.

Reactions also are possible with other supplements and herbal remedies. Saw palmetto, black cohosh or other medications that affect hormones might react unpredictably. Astaxanthin side effects such as low blood pressure and reduced calcium levels can be amplified by substances with similar effects. Use of other carotenoid antioxidants, such as beta carotene and lycopene, with astaxanthin will reduce absorption and is not recommended.

Astaxanthin Drug Interactions

Anybody taking astaxanthin should be aware of potential interactions with other drugs. One such interaction may occur if astaxanthin is mixed with nonsteroidal anti-inflammatory drugs — also known as NSAIDs. Some NSAIDs increase the risk of internal bleeding, and when combined with astaxanthin, the risk may increase.

The drug is also known to exacerbate the effect of many other medications. This includes antidiabetic medicines such as metformin and insulin, which can lead to lower blood glucose levels as well as lower blood pressure, both of which can be dangerous if left unchecked. Astaxanthin may also increase the impact of blood-thinning agents such as warfarin and asthma medications such as azelastine.

These drug interactions are the result of astaxanthin’s ability to alter the liver’s metabolization rate. Most medication is processed by the liver via enzymes that respond to a drug’s active ingredients. Astaxanthin may interfere with this process, however, by increasing the activity of these enzymes, which in turn may increase the effect of various medications and cause a dangerous drug interaction.

Astaxanthin Side Effects Hormones

In addition to its known drug interactions, astaxanthin can interfere with your hormones, too. The most significant example of this is its ability to inhibit testosterone’s conversion to dihydrotestosterone (DHT). This conversion is a process that naturally occurs in the body, but an abundance of astaxanthin may interfere by hindering the enzymes that trigger the conversion.

As a result, people taking astaxanthin will likely have a higher concentration of testosterone. In women, this may cause symptoms such as excessive body hair, hair loss, and acne. In men, it can cause high blood pressure, acne, and problems with the heart or liver. These symptoms vary widely from person to person, though, and depend on each individual’s unique biological makeup.

Interestingly, some men who take astaxanthin also report that they experience gynecomastia, or male breast development. This phenomenon is typically associated with an increase in estrogen or estradiol, but there is no clinical evidence suggesting that astaxanthin increases these hormones.

How Much Astaxanthin per Day

Despite its drug interactions and impact on hormones, there are many benefits that astaxanthin supplements can offer. It is known to support the function of the immune system, reduce the risk of cancer, and minimize inflammation. In order to take advantage of all these benefits, though, how much astaxanthin should you be consuming per day?

The answer depends on your wellness goals as well as your current health, but most supplements are intended to be taken at dosages ranging from 2mg to 12mg. Some studies have confirmed positive results in response to doses as small as 4mg per day — and other studies recommend doses as high as 24mg — so you should determine your dose based on advice from your doctor.

Remember that in addition to supplements, you can get a daily dose of astaxanthin by consuming foods that are naturally rich in astaxanthin. A serving of fresh salmon, for example, can contain 2mg to 3mg of astaxanthin. Other types of seafood such as shrimp and crab are similarly beneficial.

The Health Board is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By anon1006210 — On Feb 12, 2022

I wonder if your bodies are detoxing when you first take it. Just a thought!

By anon1006036 — On Jan 17, 2022

Astaxanthin thins the blood. That's why people are experiencing bruising, redness, swelling, etc. I'd avoid it at all costs, especially if you already have bleeding issues.

By anon1004400 — On Feb 01, 2021

Astaxanthin must vary by person.

My 80 year-old father said it helped his eyesight after 30 days of taking it--doesn't need eyeglasses in vehicle according to the eye test given by D.O.T.

My 56 year-old sister (menopausal) takes 6 mg per day of Hawaiian Astaxanthin regularly and recommends it.

I am a 53 year-old menopausal woman. I took 3 mg of Hawaiian "Supreme" BioAstin in evening and was unable to sleep. A few days later I took 3 mg in the morning and my legs felt restless so I went out for a walk and started running! I hate to run and my knees are week so this was a good increase in energy and I was able to sleep at night, but next morning I felt more nervous energy and was irritable. I went for a run again, then after 28 hours I crashed--similar to a very bad caffeine crash--meaning very tired. I am giving some of this Supreme to family members to see if they have any problems or not.

By anon1000950 — On Feb 05, 2019

I had been using 7mg natural astaxanthin daily for a few months. I noticed that I got bad headaches in the evening. I never get headaches normally, and felt very hormonal. I am post menopause 11 years. I had a CT scan (I had colorectal cancer a few years ago) and everything was clear, but they picked up a slight thickening of the womb lining. Now I have to have a transvaginal scan tomorrow (terrified) because they worry about womb cancer. I am almost 100 percent positive it is the astaxanthin that has caused my estrogen levels to go up and cause this situation.

Having had 6 years of going to hospital and a liver resection, this is another thing I don't need. I stopped this as soon as my oncologist asked me if I had used any hormones, as the penny dropped that it must be messing with my hormone levels.

By anon1000469 — On Sep 28, 2018

I've been taking astaxanthin 12 mg once daily (sourced from microalgae) for about 2.5 years. I'm not very flamingo-like yet (pink), but I'm still waiting, ha, ha (that would be pretty funny). In any case, my vision has improved significantly, particularly near field; I can read fairly small kanji without glasses, if I wish, which was very difficult, if not impossible, before (mid 50s). The effect took some time (gradual improvement). I haven't noticed any negative side effects, but who knows? I take it with DHEA, DMAE, Berberine, and Omega-3 supplements, as a set. All good, so far.

By anon1000436 — On Sep 22, 2018

What a bunch of hypocondriacs. The "side effects" that are mentioned in this article somehow manifested years ago from some quack health guru. Hardly any of them are based in reality or science. A simple search on PubMed will show you this. The hormone side effects that are mentioned are based on one study in vitro that showed Astaxanthin inhibited the 5a-Reductase enzyme. Keep in mind this experiment was done by the manufacturer of a supplement and likely would not be replicated in a living organism. Also, this finding has never been replicated in another study or mentioned anywhere else in scientific literature. There is not a single documented study of Astaxanthin lowering libido, causing breast growth or hair growth. Do you research before accepting the "facts" presented in this study.

By anon998911 — On Sep 20, 2017

I'm a male under 30 and took 5mg for only 4-5 days. It cleared my adult acne very fast, but also gave me joint pain and low libido. Other things I noticed were stronger hair and slow facial hair growth.

By anon998269 — On May 05, 2017

I took Hawaiian astaxanthin (12mg) for 7 days. After about three days, I started developing pains in my abdomen, occasional diarrhea, belching. It took me a couple of days to figure out what might be causing it (and that it wasn't just a stomach bug). I've been off it for 10 days and think I might be very slowly getting better but still have quite a bit of stomach discomfort. I did research before trying it (was using it for joint pain) and it just isn't worth it.

I've seen other people complain about stomach discomfort from it. I can't tell if it's messed with the flora in my gut, or altered the hormones in my body (both of these things seem to be side effects for some people). I have a good clean diet. I don't know if this has triggered an immune response or what yet - but just be careful, folks.

By anon997987 — On Mar 28, 2017

The reason people get blotchy skin is because the body is trying to detoxify itself, which, of course, it does by pushing out toxicity through the skin.Just cut back on the Astaxanthin but keep going with it. In time the skin will clear up.

By anon995941 — On Jun 13, 2016

I read this post and it sounds a lot like me. RE anon328680 Post 44: The reviews on astaxanthin sounded awesome with very few mentioned side-effects, so I was taking 4 mg 3 to 4 times a day for about 3 weeks. The reviews were all very positive and stated the only side-effect might be skin turning pink at high doses. How could it be the cause of my rash.

But, the description fit except for the dry skin. So, I took some NAC, MSM and R-ALA which are all suppose to detox fatty toxins. The itch has stopped for now. The rash doesn't feel as blistery. Time will tell if the rash clears.

By anon994323 — On Jan 31, 2016

I also got an eye twitch with it. More like a face twitch in my left upper cheek. I stopped the astaxanthin and the twitch went away. Just putting it out there. I'm sure it works for the people it works for.

By anon992615 — On Sep 20, 2015

I have a racing heart and a very short sleep time every time I take 4mg Astax.

By anon983367 — On Dec 29, 2014

I have been using astaxanthin for years. I started for its anti inflamitory benefits because I had tennis elbow in both elbows and a lot of pain in my thumb joints. It worked wonderfully, however, I recently ordered a different brand with a higher dosage.

I developed reflux (not heartburn, only reflux). I also developed eye twitches but I didn't attribute it the astaxanthin until I read this string of posts. When I discontinue the supplement the reflux continues for a few days and then goes away. Each time I start back, I get the reflux again. I'll have to watch the eye twitches and see if they come and go as well. Unfortunately, I ordered quite a few bottles of the higher dosage.

By anon978564 — On Nov 18, 2014

Since taking astaxanthin (3mg daily) I have developed pain in my knees and numbness along my shins. My skin has broken out and I feel tearful. On stopping the symptoms resolved rapidly. Go figure. It's obviously not suitable for everyone.

By anon956691 — On Jun 15, 2014

My gynecologist gave me Astaxanthin because I kept getting yeast infections. I told him I was masturbating at least three or four times a week. I'm a 39-year-old woman.

After taking Astaxanthin for 16 days, while forgetting for a few days, I realized that I had no urge to masturbate. I felt something was unusual when I slept beside a hot guy and felt no urge to have sex with him until he stimulated me. So I googled side effects of Astaxanthin and found out that it lowers libido.

I also sleep very badly. I wake up three to five hours after going to bed. I'm not sure if this is due to Astaxanthin or some personal stress. I've stopped Astaxanthin for three days but my libido has not come back yet! I'm waiting to see if my sleep gets better. Be careful of Astaxanthin. -- Chelsea

By anon951055 — On May 13, 2014

Did anyone on Bioastin 4mg see sudden slow appearance of tiny brown spots all over the body?

By anon950602 — On May 11, 2014

I wonder how many people realize that all these reviews are just some other supplement company doing a hatchet job on this supplement. As far as I can tell so far, this supplement is nothing short of incredible. Go read the other online reviews. They are nowhere near as negative.

By anon950529 — On May 11, 2014

Taking five mg of astaxanthin for two days resulted in severe leg cramping and a killer headache. The bottle is going in the trash.

By anon948693 — On May 01, 2014

I'm female, age 57, noticing the joint pain others here are reporting. I suspected astaxanthin was the cause some months ago and stopped. Joint pain subsided. Started again recently, and joint pain has returned. I had joint pain and inflammation from ages 40 to about 52 (tested positive for rheumatoid arthritis at age 46), but changed diet/lifestyle and got rid of it. I noticed Dr. Moore's comment here that a drop in estrogen from astaxanthin may be the cause of the joint pain, and that fish oil could help. Will try that, but am going to take a break from astaxanthin. It does help with vision, but only while you're taking it; seems possible that vision may be more blurry for a while after you stop.

But astaxanthin and other things over the past ten years have relieved me of the need to wear reading glasses, which I used to do but don't anymore.

By anon947365 — On Apr 25, 2014

I took 10 mg of astaxanthin, for over a year, as recommended to me by a health practitioner, and had wonderful positive results, lovely skin, no more sunburn, and was very happy with the results.

During that time, I also developed several health problems for which no causes were determined except for hemachromatosis, which is now under control and fortunately, there is no damage to my liver. I started to feel better and better except for two symptoms: dizziness and heart palpitation/shortness of breath. I realized it might be the astaxanthin so I quit taking it a few months ago and immediately, the dizziness and chest issues stopped. Nothing has returned at this point and I feel great ( I am 66).

Please people, be very, very careful with this powerful drug!

By anon929615 — On Feb 01, 2014

I started using Bio Astin from Hawaii last year as I have Lupus and am allergic to the sun. What a difference this product has made for me! I can go out in the sun and not develop a rash. I can now wear shorts and sundresses and not burka-like clothing. This product has completely changed the quality of my life and I'm very very grateful to have found it.

By anon926698 — On Jan 20, 2014

I'm the post 63 I had a heartburn problem after taking 1 4mg Astaxanthin after dinner for two days. I almost want to quit it. But, I want to give you my updates. I don't have heartburn anymore.

What I did is: I changed the time to take 1 soft gel after breakfast instead of dinner. I take it only three times per week to start, then, increase it gradually. I avoiding taking it on the Full moon.

My eyes feel better and can read for a longer time without feeling tired. I have more energy. I'm happy.

By anon925218 — On Jan 10, 2014

I had heartburn after I took 1 4mg Astaxanthin first day, but my eyes are getting better. So, I took another 4mg next day (yesterday after dinner), and still got heartburn. This morning, I had a headache.

By anon924631 — On Jan 06, 2014

I just bought some from Mercola, and I have taken one 4 mg capsule for only three days, and at night I have a headache, and my heart races. What's going on?

By anon347380 — On Sep 06, 2013

I have been taking Solgars and have no issues. I think everyone who has issues should tell us the brand there are taking. I have carpal tunnel and within a few days it does not bother me. I have knee pain and within a few days maybe a week of taking the pain has gone. I take five mg once a day.

So let's hear back from everyone with issues and get the brands you use, otherwise it's pointless to post comments.

By anon344510 — On Aug 10, 2013

I've been taking 12mg twice a day for two months and the only benefit that I have noticed is that I can stay out in the sun longer without getting sunburned. Other than that, I'm not sure if it's doing anything at all.

I haven't experienced any negative side effects either. The only other supplements I take are Athletic Greens, 10,000 IU Vitamin D, 2.4g EPA and 2.4g DHA from Carlson's Medomega Fish Oil, and creatine. I am a 31 year old weight lifter.

By anon343353 — On Jul 29, 2013

I've taken 4mg a day for two days now and have noticed heartburn and an overall slightly nauseated feeling, even long after taking it. This could be coincidence, of course. I came here to see if anyone else had noticed nausea and heartburn as a side-effect and it looks like the answer is no, but just for what it's worth, I'm posting this anyway.

By anon342265 — On Jul 18, 2013

I like it! I'm taking 4mg once per day after breakfast and I feel great, I'm happier and more laid back.

As with all supplements, it's probably a good idea just to take it three or four times a week.

By anon339236 — On Jun 21, 2013

Some of the bad symptoms posters have had sound similar to the "healing crisis" from other powerful algae like chlorella or spirulina or dunaliella salina.

Chlorella cleans out toxins in the body, and if you start with too much too fast, like 4 grams a day immediately, you get plenty of gas, diarrhea and maybe nausea. But these are the initial symptoms of cleaning out the toxins long built up in our bodies from pesticides and heavy metals in foods, including produce.

If you don't take any prescription drugs or have conditions commonly susceptible to interaction with microalgae like astaxanthin, then try a lower dosage like several other posters have said.

If you wait long enough, the skin blotches or other symptoms might disappear, and you'll probably keep or enhance your skin luster.

If you have a bad diet, then you're getting rid of many more toxins. The worse your diet is, the more painful and long the bad symptoms are going to be. With a better diet of whole, natural foods, that might mean less meat and dairy too, you ought to acclimate easier. Even better if you can afford organic food.

Please research the quality of at least three or more brands.

By anon338370 — On Jun 13, 2013

Astaxanthin at 4mg/day for me initially translates into increased energy followed by anxiety issues.

By anon337707 — On Jun 07, 2013

Astaxanthin is a beta carotene, and too much of it has no side effects the studies say, but remember at the time these studies were done, astaxanthin was not known, only carrots and other things. So because astaxanthin is way stronger, new studies should be done. Just look at amazon and people's ratings. It has the same side effects as Vitamin A toxicity.

By anon337193 — On Jun 03, 2013

The statement that "Anyone having adverse effects is not taking the natural astaxanthin" is simply wrong. And there are some who are allergic to it! Sure, most people can take it without any problems. But to infer that it is totally safe for everyone is absolutely foolish. And dangerous. There is nothing on this Earth that is 100 percent safe for 100 percent of the population, except drinking clean water.

In my case, I do take natural Astaxanthin and it had an adverse effect on my heart rate. I cannot take more than 12mg or my heart rate drops significantly, even though my blood pressure is completely unchanged. A female friend of mine cannot take it due to it severely lowering her heart rate even at 6mg/day and it interacts badly with medications she's on for endometriosis (maybe that involves her heart rate also, but it's unknown).

I thought in my case that maybe it was the brand as I don't usually have side effects from things. Then I tried some from a second manufacturer (the original from Hawaii) -- same effect. When I stop, my heart rate goes back to normal. My friend's heart rate went back to normal she stopped taking astaxanthin. So there are some things that people should watch for!

Here are few known ones: Low heart rate (common), not necessarily low blood pressure (low heart rate does not mean low blood pressure. This is a common myth).

Bad reaction in women or men (both researched) who take medications to correct hormone imbalances.

Reaction with some asthma inhalers (some); people with immune disorders need to be careful when taking this. It reacts badly with some of the medications to correct it.

If a person takes medications for parathyroid disorders (calcium absorption), it usually interferes with the medication negatively.

In the end, no matter what pill you might take in your life, you should always heavily research it first, from the National Institutes of Health website and talk to your doctor! But your own research is crucial because your doctor in fact does not know everything.

Do not blindly believe anyone who cannot be vouched for. They may be right, but you don't want them to be wrong! It's up to you to find out what will (or might) interact badly, and what is not going to interact with any meds that you're taking, or if you have any condition where taking something could or would make it worse. It's up to you.

By anon336945 — On Jun 01, 2013

I have been taking astaxanthin, Bioastin the Hawaiian brand, for about two months. I didn't want to take the capsules three times a day, so I took the 12mg one capsule once per day instead. My skin is glowing, my energy level is up and I find myself being able to lift heavier weights at the gym.

The side effects include slight chest discomfort following astaxanthin supplement, congested, bumpy skin on my forehead and increased back pain especially leading up to a period. I have only had one period during the this time so cannot say whether it affects the cycle, but I have not had heavy or prolonged bleeding as reported by others.

Having read a bit more about astaxanthin on various posts, I've decided to ease off the dosage to 4mg/day to see if it helps with the side effects. I really love how smooth my skin feels, so I don't want to stop taking it, however, I did start taking spirulina at the same time so not sure whether the improvements are due to astaxanthin or the spirulina supplement.

By anon336364 — On May 28, 2013

I took astaxanthin with no problems. With a diuretic, I had a severely dry mouth.

Now I'm on bioastin supreme at the same dosage twice a day. I have a severe migraine.

I will take one and see if that works after a little break. Maybe it's because of the olive oil. There are better oils to use.

By anon334856 — On May 16, 2013

I am taking astaxanthin in the mornings, and I noticed I am being very slow and sleepy. My eyes also twitch sometimes. I do not know if it is due to the use of astazanthin or not.

I am also taking Turmeric together with asta. I am reading that both are reducing blood pressure so maybe it is the blood pressure lowering effect of asta that makes me feel low on energy.

By anon331921 — On Apr 25, 2013

I have been taking 12 mg of astaxanthin (Bioastin)for a bit more than two years. I'm 72 and have had no negative side effects but several positive ones: My distance vision has improved significantly; I now must remove my eye glasses to see clearly when driving. My hair, which has been 100 percent gray for years is turning darker. My physical endurance is better than it has ever been. I have not turned pink, nor is my skin splotchy. A suntan does seem to take a lot longer to fade, though.

By anon329943 — On Apr 12, 2013

Sounds like a bunch of hypochondriacs on here. Probably just a lot of psychosomatic symptoms and totally not related - it's just a potent carotenoid. It's not mystical. It's in the same family as vitamin A, (beta-carotene) Same stuff in red fruits, veggies, etc. Just more concentrated.

By anon328680 — On Apr 05, 2013

I started taking astaxanthin three weeks ago. I developed an awful, very itchy rash that turned to small blisters and my skin became very dry. I will stop taking them today and then see if the rash disappears.

By anon325901 — On Mar 19, 2013

If I take it for too long at 4mg, I start to get joint pain and strange heart sensations/chest pain. It's probably building up in my system.

By anon314910 — On Jan 21, 2013

I have been taking Mercola's Astaxanthin for 2 years and its wonderful. It is the algae form. I have no bad side effects, some burping in the beginning, but that stopped. I think the form some of u=you are taking may be the problem. I thought a lot of the comments were funny. I have a pretty pure diet, vegetarain, I am 55 and I can vouch it really helps in the aging department. No hormonal issues, I have low blood pressure as is and have a genetic Anemia Thalasemia, and the product has not made me more anemic, nor has it lowered my blood pressure, I would certainly know. I feel great, I take 4 mg a day. Maybe you all are taking too much????

By anon313740 — On Jan 14, 2013

I am a 35 year old female who has been on the birth control pill for 15 years. I usually have very regular (can predict onset and duration to the half hour!), light, painless periods.

After two weeks of taking 4g Mercola astax daily, I got a very heavy, painful period that was eight days early and lasted 12 days. I finally linked it to the astax, stopped taking it and bleeding stopped a day later. What? It did make my skin glow and the lines disappear though! Anyone care to comment on how it might affect birth control medication/hormone levels (not just that it does)?

By anon310811 — On Dec 27, 2012

I started having sharp chest pains when taking astaxanthin. They would only last a couple of seconds and seemed to be brought on by certain movements, but I never experienced them before. I stopped taking astaxanthin and the pains never came back.

By anon309346 — On Dec 15, 2012

I took 8mg for a week. It made me very angry and reduced my libido (male). I really wanted it for its ant-oxidant properties. It did help me lose weight and helped my immune system, but I was in a horrible mood and very angry.

By anon309166 — On Dec 14, 2012

All the doctors heralding this stuff as a cure-all better start using some caveats, esp. Mercola. There definitely are side effects for some people. I'm an old geezer -- 87 -- and in excellent shape except for emphysema, for which I use an inhaler twice daily, and in some of the reading I've done, it mentions not to use this stuff while using an inhaler.

After six days of taking 5mg/day I got up one morning and the room whirled and I collapsed. This went on for two days, every time I got up from sitting or lying down. I also had an extreme backache top to bottom and had to crank up the electric blanket to be warm enough in bed. No side effects? Bah humbug.

By anon302039 — On Nov 07, 2012

I've only been on Astaxanthin for 11 days. Soon after, I started having more pain in my knees and then my hips - I thought it was due to the cold weather. Then a few days after that, I noticed visible bruising on areas where I'd felt bruised before (at 63 I seem to be going through the teen-age all elbows-and-knees syndrome of bumping into everything within reach) but the bruising never blossomed. Now I look like my husband's been beating me (has not ever happened.)

I'm stopping the stuff. I'll open the bottles and fill them with "used" kitty litter to make sure no one else gets them. So my warning is - if you notice something odd going on after you start the stuff, any stuff, stop it for a few days and see if you return to normal. You'll have your answer to "Should I be taking this?"

By anon301193 — On Nov 02, 2012

I started using Astaxanthin from Now. It is an all natural product. I was taking it for my eyes to get relief from pterygium (tissue growth on the eyes). When I take it, I get blinding migraine headaches. My head hurts on the inside and I have to have absolute darkness. The migraines are lessening in intensity as time goes on. My eyes have not cleared up, however, and I don't know if it's working. I'll take a few days off to see if everything stops, then try again.

By anon296677 — On Oct 12, 2012

I've been seeing a lot of posts on other sites by people using it to avoid sunburn effects. I wonder if they're still getting UV exposure and thus higher risk of cancer now, as they're spending more time in the sun. Those sunburns are a natural deterrent to keep one out of the sun.

By anon295560 — On Oct 06, 2012

I started using astaxanthin with salmon oil from Vital Choice. I developed splotches on my cheeks which then went away. I only used it for two weeks so I am not sure if it is the astaxanthin that caused it. I am going to stop and see if any splotches return. If not, I will stop for a week or two and then see if using axtaxanthin 4mg causes a return. --Judith 23

By anon282915 — On Aug 01, 2012

I found this post by searching under "Menstrual Issues Astaxanthin," which should give you a good idea what's going on with me.

I started taking 4mg (daily) of natural Astaxanthin three months ago. The first 2 1/2 months were completely uneventful, and I was loving the benefits to my skin, and even detected improvements in my aerobic capacity.

Three weeks ago, I started getting a bruise on my right cheekbone, then, a week later, a larger bruise on my left cheekbone. I wasn't sure what as going on exactly, but also wasn't alarmed (apparently I should have been).

My menstrual cycle was a week late, although again, I wasn't worried because that can happen. However, when it arrived, it was heavy. Very heavy, which is highly unusual for me.

Additionally, my usual four day period lasted for eight (eight!) days. When I stopped taking Astaxanthin, it stopped the next day.

Much to my chagrin, two days later it started again, and is very heavy. All of this has made me anemic and pretty light-headed, which is never a good thing.

I have to say, *if* I ever go back to taking Astaxanthin, it will only be twice a week at the most, definitely never, never every day again.

By anon277848 — On Jul 02, 2012

I have been taking 10mg of astaxanthin since mid March. I have found it very beneficial for inflammation. I lost 15 pounds in two weeks! I also have noticed a great improvement in my eyesight! I was to the point pier to taking the astaxanthin of needing a stronger script for my eyes. Now I see crystal clear!

I highly recommend this product to everyone! Oh also, I went off all prescription drugs while starting the astaxanthin so I have absolutely no side effects!

By anon275294 — On Jun 17, 2012

Some of the posters here appear to be taking ridiculously high dosages, like 8mg/day. No wonder they are seeing side effects. Newsflash: Human consumption of astaxanthin pills is still pretty new territory. If you're going to be your own guinea pig, love yourself and take it slow.

I am going to follow Dr Sahelian's advice and start very slow: 2mg, three times per week, and take a week off every month. We'll see how it goes.

It's also been around the Internet that this stuff can be used topically on age spots. That might be a safer way to start, but again, start small.

Don't be put off by the fishy smell. Natural astaxanthin is derived from marine algae, so that's how it's supposed to smell.

By anon272700 — On Jun 02, 2012

This is Dr. Moore in Texas. The most likely reason for the joint pain is a reduction in estrogen. This is a common side effect with all drugs and supplements that lower estrogen in the body. You can either reduce the dose and or add fish oil for relief.

By anon271763 — On May 28, 2012

To all the people that are trying to see the benefits of astaxanthin, if you are having side effects, try Turmeric or more specifically curcumin supplements. The best brand is Thorne and can be purchased from Amazon. Read about turmeric. It has so many similar benefits and is completely safe and has been used for thousands of years in traditional medicine. I use it and it has been wonderful. Good luck to all!

By anon271656 — On May 27, 2012

Astaxanthin's full effects on human health are still unknown, therefore it is best to practice caution and use in moderation (although we don't even know what that would be).

Considering that my gorgeous skin comes with the price tag of a racing heart/ palpitations, it's probably a good indication that I need to take a break, maybe an extended break until more studies are completed on this super antioxidant. If it's unnatural for humans to get 4mg of astaxanthin through our diet, should we bombard our bodies with such a supplement at all?

By anon269948 — On May 20, 2012

I have been taking anywhere from 2 mg to 6 mg of naturally derived astaxanthin.

Pros: It seems to have helped my body use insulin that another medicine I take has caused my body not to be able to access properly. It also has helped with inflammation, specifically arthritis-type pain in my hands, and has provided me with more energy.

Cons: I have developed a cardiac arrhythmia (skipping a beat regularly) and moderate to severe back pain between my shoulder blades. In addition, the "more energy", if I take the supplement before trying to sleep, translates into insomnia (it keeps me awake until it wears off). Just FYI.

By anon267979 — On May 12, 2012

I am a 41, insulin-dependent diabetic with fair skin. I began taking it at 2mg twice a day. Within four days, my body developed a nasty red rash on my arms, thighs and bottom. It was so itchy. It took over a week to get the rash to light pink!

We are all different, but be cautious when taking this product. I was taking a brand that I think was called Good Source from GNC. If you develop the rash, try Arnica gel. That helped my rash and helped with the ugly redness.

By paleogirl111 — On Mar 22, 2012

Has anyone taken this supplement and had it affect their menstrual cycle? Unfortunately, in my excitement to try this wonder supplement I neglected to check on the "side effects" before taking 8 mg a day. Well, I've just passed my 30-plus day, and I did not have my period. I am not pregnant, or peri-menopausal.

Needless to say, when I checked the side effects I was shocked to see that it specifically mentions "hormone changes." Well, what exactly does that mean? I am no longer going to take this supplement and am hoping that soon my regular cycle will return. I am very disappointed! I used the product on Dr. Mercola's website.

By alicethegeek — On Mar 15, 2012

My sister and I started taking 4 mg Now Astaxanthin (from algae) in early March. We are in our 30s. She wears glasses and was hoping for better vision. I have sun damage, i.e., age spots that I was hoping to get rid of. I was also looking forward to the added sun protection. What happened instead was that we both experienced severe back pain after about six days. We didn't think it was the astaxanthin. I thought it was the way I slept or the mattress, but I was lazy and didn't take astaxanthin one day and the pain went away. I took it the next day and the back pain returned.

My sister complained about her back and her entire spine hurting. As a result, she had to take time off work because she couldn't move her back. She lay in bed all day. That's when I wondered if we were both reacting to the astaxanthin adversely. I told her to stop taking astaxanthin. The next day, we were both free of back pain. Reading this article helped me understand why we had back pain. Calcium was being removed from our bones -- enough to cause back issues.

For those of you who are benefiting from astaxanthjn, what age range are you? I'm wondering if it can be harmful when under a certain age and extremely beneficial beyond another age.

It would be great if people also detailed the brand and lot number when leaving a review. That way we can see if there are issues with a brand or lot/batch. I have the Now Astaxanthin Lot#1424341 1110 Best by 12/2014.

By anon252396 — On Mar 05, 2012

My partner took 8 mg for about a month and developed a twitch in her left eye. I had her stop taking it and the twitch was gone in three days. She restarted and after four days, the twitch returned.

I took 8 mg for about 45 days and developed a heart arrhythrmia that stopped after I discontinued the uses but returned after a restart. We were taking BioAstin.

By health123 — On Feb 09, 2012

I'm wondering if one has to go through a little pain to heal and hence the negative side effects that some are seeing.

When we exercise, we try to achieve a burn to build muscle. Not sure that is the best example, but whenever we get sick it's a good thing such as running a fever because our immune system is working to make us better. No pain, no gain.

By anon224028 — On Oct 21, 2011

I used astaxanthin, and not only had swelling, and pain in knees, but my legs swelled up like fire hydrants. I do believe there should be mandatory testing before these products are allowed on the market.

By anon223455 — On Oct 19, 2011

Took the real Astaxanthin 4mg from DrMercola website, only two days and my knee joints began to hurt really bad. I stopped it. Three weeks later, my knees stopped hurting and I tried it again to make sure it was the Astaxanthin. Again second day my knees are stiff and painful. I now believe that is my side effect. Sad, but true.

By anon203634 — On Aug 06, 2011

Anyone having adverse effects is not taking the natural astaxanthin, but is taking a synthetic type. You are not to take over 12mg per day, 8mg is ideal. If you pick it up locally, ONLY get it at your local health food store. If you get it online, shop through Amazon and read the reviews and get the natural astaxanthin. Any of you who have had negative effects are most definitely taking the synthetic, and do not overdo it. Anything in excess is bad for the body. This supplement is excellent for the skin, for the joints, and for the brain!

Be smart and don't just buy any brand. The natural type works wonders. The only warning I would have is make sure you're aware of your asthma medications and its affects with astaxanthin. If you find yourself needing your inhaler more, reduce your dosage.

By anon195554 — On Jul 12, 2011

After two years of extreme stress, I became sensitive to the sun to the point of breaking out in hives with even a minute's exposure. I began taking 8 mg astaxanthin two weeks ago and went out in the sun this week for 15 minutes. I ended up without redness or hives. For me, this is a miracle! I'm a believer and will continue taking natural astaxanthin.

By anon193523 — On Jul 05, 2011

I took the Astafx version of Astaxanthin for 30 days (canceled my "membership" with the company immediately upon receiving the bottle, though, because I read horror stories about how they'd keep charging your credit card unexpectedly).

Anyway, I was pleased with the product. I have one deep frown line at the top corner of one eye, and some other fine lines underneath my eyes. After taking the astaxanthin, as well as keeping a very strict, morning/night facial routine, the deep line isn't as noticeable, and the fine lines are virtually nonexistent.

Again, I was taking the supplement and using facial serums/creams. So I can't say it was all due to the astaxanthin. However, I've been using facial stuff for years with no luck on that darn frown line. So I feel positive that the astaxanthin is what did the majority of work on that.

By anon192870 — On Jul 02, 2011

I learned about it from a doctor at JHH in Baltimore, MD. He recommends it to his patients for eye disorders.

I think that just about says it all. I ordered it in mid-May 2011, originally took two a day for 30 days, 8 mg, then I went to one a day. I have not taken a break off of it yet. But I'll say this much, and this is no hype: I actually saw a difference in my vision. I have to actually get a new weaker script for my contacts in one of my eyes. It did not have the same effect on both eyes. I will go off of it for seven days starting next week, just to see if anything changes in that time frame.

By anon182886 — On Jun 03, 2011

For those who are reporting negative side effects, have you considered the source of the astaxanthin? Are you taking the real thing, sourced from microalgae, or have you possibly taken a synthetic version, made from petrochemicals? Just something to consider.

By anon176401 — On May 15, 2011

I read some comments and didn't see anything like my side effects. I have been taking this for three months and i loved it in the beginning. But, now i have a lot of pain in my joints. I don't know if comes from astaxanthin. However, i am thinking about stopping for another two months and see what happens. If anybody out there feels the same please, let me know. --pinto11

By anon175867 — On May 13, 2011

I've been using the stuff for a couple of months. I took it initially to improve my eye reflex time for tennis. I think it has worked there. I also work out with weights and have had a very nice result there, too. Things seem easier and I have increased my weights on routines significantly. My complaint would be that I seem "laid back' and less aggressive in my tennis.

By anon159078 — On Mar 10, 2011

What are the interactions of astaxanthin with other medications ( e.g., meds for cholesterol, high blood pressure etc.). It seems that there are no studies to document negative interactions with medications. Certainly that is key to whether anyone would want to use astaxanthin as a supplement. It sounds like a too good too be true health source.

By anon158325 — On Mar 06, 2011

I used it for a few days then I stopped right away. by taking three per day as (recommended/allowed) by "astaxanthin Hawaii" I started developing "juicy pimples" on my face. I opened one of the gelatin and inside you have a sticky reddish oily substance inside.

I don't know. Now I will take one caps once a week without the thick black gelatin that comes with it because it's probably made with pork.

By anon154217 — On Feb 20, 2011

Don't take it. It's toxic and harmful. Please, do more research folks before buying in to the millions of dollars put in to it's advertisements.

By anon149397 — On Feb 04, 2011

i have been taking astaxanthin for about a month or two now, and in the last few weeks have noticed odd splotches on my face. Very ugly. I think I am going to stop taking it. Normally my skin is pretty clear.

By closerfan12 — On Dec 15, 2010

I had heard that using astaxanthin for skin products was actually not a good idea. A friend of mine said that she had read an article where several people had had really terrible reactions to astaxanthin antioxidant serums that they had gotten online.

And the same article said that it's actually pretty easy to build up an astaxanthin toxicity level, since it's a fat soluble material, and so it doesn't get put out of the body if you take too much. Rather, it just gets stored in your fat cells, and if you start to lose weight or those fat cells are burned off, then all the astaxanthin can be released into your system, causing serious issues.

Have you guys heard of anything like this, or tried something like this?

By musicshaman — On Dec 15, 2010

But you know, there really are a lot of astaxanthin benefits too.

For instance, astraxantin really is a strong antioxidant. Many astaxanthin antioxidant products are going to give you a better effect than any amount of plumping collagen products out there on the market right now because it can help prevent sun damage from occurring to begin with, and can also improve your skin's tone and coloring.

Besides, it's also really good for your body. Astaxanthin can go into almost every part of your body, even across the blood-brain barrier, so you can get its protection in virtually every organ of your body.

And even though it does have its side effects, look at the side effects for comparable treatments -- they can be really crazy too.

So even though astaxanthin is powerful, and you should use it properly to avoid the risk of serious side effects, if you do it right, it can be a great treatment and cosmetic.

By Charlie89 — On Dec 13, 2010

That's so funny that one of the side effects of astaxanthin is messing up your skin, because I just saw a one of those anti aging serums with astaxanthin in it.

It claimed that astaxanthin was an antioxidant, and could be used to reverse the signs of aging, get rid of lines, etc.

But how can that be true if it is supposed to cause problems with your skin to begin with? Because the way I read it, you could start taking an astaxanthin supplement for your wrinkles and end up with odd splotches on your skin.

Am I right, or is there more to this than I know? Anybody have any idea?

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