If you are weighing Prevagen for yourself or for a parent who has been more forgetful lately, you deserve a straight answer before you spend money. Prevagen is a real, over-the-counter supplement that Amazon customers rate around 4.4 out of 5, but the outside research on its main ingredient is limited, and a federal court has barred its maker from claiming it improves memory or brain function. Below we set out what the brand says, what the research found, what it costs, how refunds work, and how it compares with one other option, so you can decide.
Disclosure: this page contains an affiliate link. If you buy through it, this site may earn a commission at no extra cost to you.
Is Prevagen legit, and what does it claim?
Yes, it is a real product sold over the counter. The brand’s website calls Prevagen “a supplement made for your brain” and says it is “an over-the-counter supplement for healthy brain function and memory improvement.” The package adds that it supports “healthy brain function, sharper mind, and clearer thinking.” The website also says Prevagen is not intended to treat or prevent disease, and that it has met the standards for NSF’s Contents Certified certification program. Its disclaimer says the statements are “Based on a clinical study of subgroups of individuals who were cognitively normal or mildly impaired.”
The maker is Quincy Bioscience. The brand’s site says Prevagen has been sold since 2007, that it does not require a prescription, and that it is the “#1 dietary supplement in drug stores.” That last line is the brand’s own statement.
What is in Prevagen?
Prevagen has two active ingredients. The brand says apoaequorin was “Discovered in jellyfish” and is now “produced in a controlled scientific process.” The other is vitamin D3. Per capsule, the product listings show:
| Strength | Apoaequorin | Vitamin D3 |
|---|---|---|
| Regular Strength | 10 mg | 50 mcg (2,000 units) |
| Extra Strength | 20 mg | 50 mcg (2,000 units) |
| Professional Formula | 40 mg | 50 mcg (2,000 units) |
The label directions are one capsule a day, in the morning, with or without food. The maker recommends at least 90 days to decide whether it is working for you. For a closer look at the label and the ingredients, read our prevagen ingredients guide.
Does Prevagen really work for memory?
Outside sources say there is no reliable evidence that apoaequorin boosts your memory. The study the brand has pointed to is on PubMed as the apoaequorin verbal learning study, titled “Effects of a Supplement Containing Apoaequorin on Verbal Learning in Older Adults in the Community.” Some researchers said it showed slight improvements on a few memory tests compared with the placebo group, in people with little or no cognitive impairment. They concluded that Prevagen could “improve aspects of cognitive function” in people with normal brain-related aging or very mild cognitive impairment. Some neuroscientists said it did not show that people who took Prevagen benefited significantly more than the placebo group.
Outside writers add that it was one small study and that the maker sponsored it. Experts usually do not treat one small study as proof. They also note that a sleep study the company cites found people who slept fewer than 7 hours a night and took Prevagen daily for 3 months gained an average of 37 minutes of sleep a night. That study did not list the dose and was not blinded or placebo-controlled.
On digestion, a 2014 laboratory study found that more than 90% of apoaequorin is broken down into amino acids by pepsin, a stomach enzyme, within 30 seconds. Outside writers say there does not appear to be any study showing that apoaequorin taken by mouth reaches the brain.
Vitamin D has its own research. A 2017 study titled “Vitamin D and memory decline: Two population-based prospective studies” found a possible link between moderate or severe vitamin D deficiency and visual memory loss. For background on vitamin D and brain function, see this 2012 vitamin D and brain function article. Outside writers also note that the vitamin D in Prevagen matters most for someone who is deficient.
Why don’t doctors recommend Prevagen?
The reason comes down to the research. Most health experts advise against taking supplements that claim to improve memory. The Alzheimer’s Association cautions that claims about memory-enhancing dietary supplements are mostly based on very little science. A group of scientists, doctors, scholars and policy experts brought together by AARP said it could not recommend any ingredient or supplement marketed for brain health, and it concluded that a healthy diet is the best way to get brain-boosting nutrients.
What about the lawsuit and the FTC?
In 2017, the Federal Trade Commission and the state of New York took legal action against Quincy Bioscience, citing an ad campaign that said Prevagen was “clinically shown” to improve memory. In December 2024 the FTC and the New York attorney general won the case. A federal judge ordered the marketers to stop eight marketing claims because of a lack of scientific support, and the makers are now barred from claiming that Prevagen improves memory or brain function. After the 2024 ruling, the FTC said that health claims need to be backed up by reliable scientific evidence.
The FDA and FTC say supplement makers are not supposed to claim their products can treat or prevent illnesses or chronic conditions. The FDA has not approved Prevagen for memory loss. The brand’s own wording still includes “memory improvement,” so keep the court order in mind as you read its pages. A lawsuit filed in 2023 also said counterfeit versions of Prevagen were sold on Amazon, so check the seller name on any listing before you buy.
What do Prevagen reviews and complaints say?
Customer reviews
Prevagen’s own site features customer quotes such as Steve S.’s “Prevagen works for me so far. It’s a help for sure.” and Carolyn R.’s “I have been using Prevagen at least 6 to 7 years and I wouldn’t be without it.” The site says that “Every review is from a verified buyer.”
On Amazon, the Prevagen Regular Strength 3-pack listing showed a 4.4 rating from 13,311 reviews and about 300 sold a month on November 10, 2026. Those are the listing’s own figures. They show how many people bought and rated the product, not whether it works for you.
Complaints and reported side effects
Outside summaries of reports on Prevagen list these side effects:
- Headache, dizziness and nausea
- Constipation and swelling
- High blood pressure and nervousness
- Memory problems and trouble sleeping
Two word-of-mouth reports from people with multiple sclerosis described low blood pressure, and depression with suicidal thoughts. It is not clear whether apoaequorin caused either one. If you or someone you care for has new mood changes or other new symptoms after starting, contact a clinician soon.
Who should not take Prevagen, and what about the liver?
Outside summaries say the safety of Prevagen “hasn’t been well studied.” Its makers say it is not intended for people with moderate or severe memory loss. Ask a clinician first if you take prescription medicines, are pregnant or nursing, are under 18, have a liver condition, or have surgery scheduled. For liver concerns in particular, ask a pharmacist or clinician to check Prevagen against your health history and your medicines.
If you already take a vitamin D supplement or a multivitamin, ask a pharmacist how much total vitamin D you get each day.
How much does Prevagen cost, and how do I buy it?
Prices as of November 10, 2026, from Amazon listings. Prices and bundles change, so check the listing for today’s price.
| Amazon listing | Supply | Price shown |
|---|---|---|
| Prevagen Regular Strength with Storage Box, 30 Capsules, 3-Pack | 3 months at one a day | $102.47 |
| Prevagen Regular Strength with 7-Day Pill Minder, 30 Capsules, 3-Pack | 3 months | $107.85 |
| Prevagen Regular Strength with 7-Day Pill Minder, 30 Capsules, 2-Pack | 2 months | $73.90 |
| Prevagen Extra Strength with 7-Day Pill Minder, 60 Capsules, 1-Pack | 2 months | $99.95 (list $109.90) |
| Prevagen Professional Formula with Storage Box, 30 Capsules, 1-Pack | 1 month | $84.95 |
| Prevagen Regular Strength Mixed Berry Chewables with Storage Box, 30 Tablets | 1 month | $37.95 (list $39.95) |
The brand’s own site says it offers free shipping on orders over $50, subscribe and save on all Prevagen products, and Prevagen Rewards savings available only on its site. Before you buy, ask the brand for its return terms in writing, since refund rules matter most if the product is not right for you. The maker’s recommended 90 days lines up with a 3-month bundle, if you want to follow its suggested trial length.
Is there anything better than Prevagen? A fair look at MemoFix
We compare the options on points you can check: ingredients, directions, price, refund terms, shipping and the cautions on each label. MemoFix is one option. Here is what its label and site say.
MemoFix is a dietary supplement sold as 60 capsules, two a day. The seller markets it for memory and concentration. Its label lists these ingredients per two capsules, and the seller describes each one as follows:
| Ingredient | Per two capsules | Seller’s description |
|---|---|---|
| Branched Chain Amino Acids 2:1:1 (L-Leucine, L-Isoleucine, L-Valine) | 540 mg | “commonly featured for everyday energy and focus” |
| Bacopa Monnieri Extract | 200 mg | “traditionally used to support memory retention and mental clarity” |
| Rhodiola Rosea Extract (3% Salidroside) | 100 mg | “traditionally used to help the body feel balanced and resilient” |
| L-Theanine | 100 mg | “frequently included to support calm, focused attention” |
| Panax Ginseng Extract | 90 mg | “traditionally valued to support mental clarity and everyday vitality” |
Ingredient research does not prove that a finished capsule works, for either product. To judge MemoFix, ask the maker for the studies behind each ingredient at the doses listed, and have a pharmacist check all five ingredients against your medicines. The label says pregnant or nursing mothers, children under 18 and people with a known medical condition should consult a physician before using it, and that you should not exceed the recommended dose.
MemoFix’s FAQ says it is manufactured in an FDA-registered facility, and the FDA does not approve manufacturing facilities; see the FDA website for more.
MemoFix prices and bundles
MemoFix’s order page, as captured October 6, 2026, lists these bundles. Each bottle holds 30 servings, so one bottle lasts 30 days at two capsules a day.
| Bundle | Price per bottle | Total | Shipping |
|---|---|---|---|
| 2 bottles | $79 | $158 | $9.99 |
| 3 bottles | $69 | $207 | Free |
| 6 bottles (labeled Best Value) | $49 | $294 | Free |
To check today’s price or place an order, go to the Product Page. The 2-bottle bundle is the smallest order on the page.
How do MemoFix refunds work?
MemoFix offers a 60-day money-back guarantee. Your return authorization must be requested and approved within 60 days of purchase. Email contact@getmemofix.com with your order number, the email address used on the order, and your receipt or proof of purchase. Then ship the bottles back within 14 days of receiving the authorization, and email the tracking number. The seller says to send back all the bottles, even if they are empty, for a full refund. For a change of mind, you pay return shipping. If the item arrived damaged, defective or incorrect, MemoFix says it pays return shipping after you email a photo. Its FAQ says shipping is available worldwide and the maximum delivery time is 30 days.
Side by side
| Point | Prevagen | MemoFix |
|---|---|---|
| Ingredients on the label | Apoaequorin 10 mg, 20 mg or 40 mg by strength; vitamin D3 50 mcg | Five ingredients per two capsules (see the table above) |
| Daily directions | One capsule a day, in the morning | Two capsules a day with an 8 oz glass of water; the label suggests 20 to 30 minutes before a meal |
| Supply per bottle | 30 days for a 30-capsule bottle at one a day | 30 days (60 capsules at two a day) |
| Price | See the Prevagen price table above | $49 to $79 a bottle, depending on bundle |
| Refund | Ask the brand for its return terms before you buy | 60-day money-back guarantee; you pay return shipping for a change of mind |
| Shipping | Brand site says free shipping on orders over $50 | $9.99 on the 2-bottle bundle, free on 3 and 6; delivery up to 30 days |
| Maker’s description | “healthy brain function and memory improvement” | Marketed for memory and concentration |
| Ingredient research | Outside writers call the apoaequorin research limited; the memory study was small and maker-sponsored | Ask the maker for studies on each ingredient at these doses |
| Label caution | Brand says it is not meant to treat or prevent any disease | Pregnant or nursing, under 18, or a known medical condition: consult a physician first |
The honest differences are these. Prevagen has been on sale since 2007, according to its site, and its claims have been the subject of a court order. MemoFix lists five ingredients with an amount for each, and it spells out its refund steps. Prevagen’s directions are one capsule a day; MemoFix’s are two. Neither product’s ingredient research settles whether it will work for you, so ask each maker for its studies before you order.
How do I improve my memory without a supplement?
Cleveland Clinic says memory changes can be a normal part of aging, and that everyday habits can help you stay sharp over time. Its tips cover sleep, exercise, balanced nutrition and stress management, and Cleveland Clinic memory tips go through them in detail. Harvard Health’s Harvard Health focus and memory tips suggest looking at the person and listening closely, repeating back what you heard, choosing quiet places to talk, and doing one thing at a time.
We suggest keeping one simple log for a few weeks, so you and your pharmacist or clinician have real examples to work from:
| Date | What was forgotten or missed | Hours of sleep | Pills and supplements taken |
|---|---|---|---|
| Example: Monday | Forgot the name of a neighbor | 6 | Morning pills and one supplement |
When memory needs a provider now
Cleveland Clinic says it is time to talk with a healthcare provider if memory problems start to interfere with daily life, such as forgetting to pay bills or getting lost in familiar places. Make that call before you rely on a supplement.
Before you order
- Check today’s Prevagen price on the listing or the brand’s site, and ask the brand for its return terms in writing.
- Check the seller name on any Amazon listing, given the 2023 counterfeit lawsuit.
- Ask MemoFix for the studies behind each ingredient at the doses on its label.
- Take your medicine list and the label of every supplement to a pharmacist, including vitamin D.
By the Senior Safety Desk Editorial Team
This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.