St. John's Wort and Your Medicines: What Every Memopryl Buyer Should Check
Quick answerSt. John's wort is one of six named Memopryl ingredients. It speeds up the enzymes that clear many drugs, so it can weaken birth control pills, warfarin, cyclosporine, digoxin and some HIV, cancer and seizure drugs. With antidepressants it can cause serotonin syndrome. If you take any prescription, ask your pharmacist before your first capsule.
Why is St. John's wort in Memopryl?
St. John's wort is a yellow-flowered plant, Hypericum perforatum. It is one of the six ingredients named on the brand's "Inside Memopryl" graphic. The others are phosphatidylserine, ginkgo leaf, N-acetyl L-carnitine, bacopa and L-glutamine.
What it is studied for
Research on St. John's wort centers on mood, usually at 300 mg three times a day, or 900 mg in total (StatPearls, St. John's Wort). It is not a memory ingredient. Memopryl makes no mood claim, and nothing here suggests it treats low mood.
How much is in the capsule
The amount is not published in our files, because the Supplement Facts panel was not part of them. For interactions, that detail matters less than you might think. The herb is present, so the medicine check still applies.
How does St. John's wort change the way medicines work?
St. John's wort changes how fast your body clears many medicines. It switches on liver and gut enzymes that break drugs down (StatPearls, St. John's Wort). The result is less medicine in your blood than your doctor planned for.
Why weaker can be dangerous
A weaker dose is not a small problem for some drugs. A blood thinner that stops working well, or a transplant drug that drops too low, can have serious results. That is why NCCIH calls out these interactions so clearly (NCCIH, St. John's Wort).
Starting and stopping both count
Because the effect builds and fades, adding or dropping the herb can shift your medicine levels. Tell your prescriber before you start a product that contains it, and before you stop one.
Which medicine groups does St. John's wort affect?
The table groups the medicines that sources name most often. It is a starting point for a talk with your pharmacist, not a full list. Many other drugs use the same enzymes.
| Medicine group | Examples named | What can happen | Source |
|---|---|---|---|
| Birth control pills | Hormonal contraceptives | The pill may fail; unplanned pregnancy is possible | (MSKCC, St. John's Wort) |
| Blood thinners | Warfarin | Weaker effect; clotting levels need monitoring | (NCCIH, St. John's Wort) |
| Transplant drugs | Cyclosporine | Lower drug levels | (NCCIH, St. John's Wort) |
| Heart medicine | Digoxin | Lower drug levels | (NCCIH, St. John's Wort) |
| HIV medicines | Some HIV drugs | Weaker effect | (NCCIH, St. John's Wort) |
| Cancer medicines | Some cancer drugs | Weaker effect | (NCCIH, St. John's Wort) |
| Cholesterol medicine | Simvastatin | Weaker effect | (StatPearls, St. John's Wort) |
| Seizure medicines | Some seizure drugs | Weaker effect | (StatPearls, St. John's Wort) |
| Antidepressants and serotonin drugs | SSRIs and similar drugs | Serotonin syndrome risk | (MSKCC, St. John's Wort) |
Checked your medicines? See Memopryl options
60 capsules per bottle, prices at checkout and a 60-day money-back guarantee. Please clear St. John's wort with your pharmacist first.
What is serotonin syndrome, and who is at risk?
Serotonin syndrome is a reaction to too much serotonin activity in the body. It usually comes from mixing drugs or products that raise serotonin. St. John's wort taken with SSRIs or other serotonin drugs is a known trigger (MSKCC, St. John's Wort).
Signs to know
Symptoms can include confusion, a racing heart, sweating, shaking, muscle twitching and a high temperature. They can come on within hours of a new combination. These signs need urgent medical care.
Who should be most careful
Anyone taking an antidepressant or another drug that affects serotonin should talk to a doctor first. Do not combine them on your own.
Antidepressants and St. John's wort
If you take an antidepressant, do not start a product with St. John's wort without your prescriber's approval. Never stop an antidepressant on your own to make room for a supplement.
Does St. John's wort cause sun sensitivity?
St. John's wort can make skin more sensitive to sunlight (MSKCC, St. John's Wort). Some people burn faster or get a rash on exposed skin. Fair skin and long hours outdoors raise the odds.
Use sunscreen and cover up on bright days. If a new rash or strong burn appears, stop the product and call your doctor. Our side effects page covers the other ingredients' effects.
How do the other Memopryl ingredients compare on interactions?
St. John's wort is the Memopryl ingredient with the most interactions, but not the only one worth a check. Ginkgo matters for anyone on a blood thinner. Bacopa may touch the same enzyme system in a smaller way.
| Ingredient | Medicine concern | Common side effects | Source |
|---|---|---|---|
| St. John's wort | Weakens many medicines; serotonin syndrome with serotonin drugs | Sun sensitivity | (NCCIH, St. John's Wort) |
| Ginkgo leaf | May raise bleeding risk with blood thinners | Bleeding concern | (NCCIH, Ginkgo) |
| Bacopa (Brahmi) | May affect drug-processing enzymes | Nausea, cramps, more stools | (StatPearls, Bacopa) |
| N-acetyl L-carnitine | None highlighted in our sources | GI upset and fishy odor at about 3 g | (NIH ODS, Carnitine) |
| L-glutamine | None highlighted in our sources | Nausea, headache | (MSKCC, Glutamine) |
| Phosphatidylserine | None highlighted in our sources | Not covered in our sources | (Kato-Kataoka et al., 2010) |
Our article on what the big ginkgo trials found covers the bleeding question in more detail.
How do you ask your pharmacist about Memopryl?
Your pharmacist is the fastest expert to ask, and the visit is usually free. Bring the right things and the check takes a few minutes.
Bring the bottle
Show the Memopryl bottle or the ingredient list. Point out St. John's wort and ginkgo.
List everything you take
Include prescriptions, birth control, over-the-counter drugs, vitamins and other herbs.
Ask three questions
Does it weaken any of my medicines? Could it raise serotonin or bleeding risk? Should my doctor know?
Mention the missing amounts
Say that the per-capsule amounts are not published, so the pharmacist can judge with that in mind.
Write down the answer
Keep a note with the date and the pharmacist's advice with your medicine list.
If you want to read the panel first, our guide to reading a label without amounts explains each line. Questions about an order go to the desk on the contact page.
What if you already took Memopryl with a medicine?
If you already took Memopryl alongside a prescription, stay calm and make a call. Most people simply need advice on what to do next. Do not guess, and do not change your prescribed medicine on your own.
Stop the supplement for now
Set the Memopryl bottle aside until you have talked to a professional. Keep taking your prescribed medicine as directed.
Call your pharmacist or doctor
Say which medicines you take, when you started the capsules and how many you have taken.
Use backup birth control if needed
If you take the pill, ask whether you need a backup method for a while.
Watch for warning signs
Unusual bleeding or bruising, or signs such as confusion, a racing heart or a high temperature, need urgent care.
If you decide the product is not for you, the guarantee page explains the 60-day refund steps.
Who should skip Memopryl or ask a doctor first?
Some people should skip Memopryl or get a clear yes from a doctor first. The label is for adults, and the herb's interaction list is long.
Under 18
Memopryl is for adults only.
On a listed medicine
Birth control, blood thinners, transplant, HIV, cancer, heart, cholesterol or seizure drugs.
On an antidepressant
Or any drug that affects serotonin. Ask your prescriber first.
Pregnant or nursing
Ask your doctor before taking any herbal supplement.
Our who it's for page covers the adults this product suits and the ones it does not.
St. John's wort and medicines FAQ
Why is St. John's wort in a focus supplement?
The brand lists it as one of six named ingredients. It is studied mainly for mood, not memory, and Memopryl makes no mood claim.
Which medicines does St. John's wort affect?
NCCIH lists birth control pills, warfarin, cyclosporine, digoxin, some HIV and cancer drugs and some antidepressants. Sources also name simvastatin and some seizure drugs.
Does a small amount still matter?
Treat it as if it does. The amount in Memopryl is not published in our files, and interactions depend on the herb being present, so a pharmacist check makes sense either way.
What is serotonin syndrome?
It is a serious reaction when too much serotonin activity builds up, often from mixing drugs. St. John's wort with SSRIs or other serotonin drugs can trigger it.
Can I take St. John's wort with birth control pills?
It can make the pill less reliable. Talk to your doctor or pharmacist, and ask about a backup method, before taking any product that contains it.
Should I stop my medicine to try Memopryl?
No. Never stop or change a prescribed medicine on your own. If the two do not mix, skip the supplement.
Does St. John's wort make you sunburn faster?
Memorial Sloan Kettering lists sun sensitivity as a possible effect. Use sun protection, and tell your doctor if you notice unusual skin reactions.