Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

Phosphatidyl Serine 150 mg Soy-Free Ingredients & Drug Interactions

by NOW

Phosphatidyl Serine 150 mg Soy-Free label
See full label image
Capsule Category: Fat/fatty Acid
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Phosphatidyl Serine 150 mg Soy-Free against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Major

Phosphatidyl Serine 150 mg Soy-Free is a dietary supplement by NOW with 2 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis prevention, dietary calcium deficiency, heartburn relief (calcium carbonate antacids).Based on those ingredients, 387 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Phosphatidyl Serine, Calcium. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Phosphatidyl Serine 150 mg Soy-Free by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Phosphatidyl Serine 150 mg Soy-Free by NOW — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Phosphatidyl Serine 150 mg Soy-Free by NOW

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Sep 3, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • “Calcium” is listed as a grouped ingredient — the label gives one combined amount (40 mg) without saying how much of each component you get.

This product contains two active ingredients: calcium carbonate and phosphatidyl serine, each contributing a different role. Calcium carbonate is a well-absorbed form of calcium, an essential mineral for bone strength and many body functions.

Phosphatidyl serine is a phospholipid — a type of fat found naturally in cell membranes — thought to support brain and cognitive function. The capsule also contains several inactive ingredients (hypromellose, microcrystalline cellulose, magnesium stearate, silicon dioxide, stearic acid, croscarmellose sodium, and ascorbyl palmitate) that serve as binders, flow agents, and capsule material.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Memory and cognitive support.
  • We looked for evidence on: Age-related cognitive decline, Alzheimer disease, Cognitive function, Dementia, Mental performance, Attention and focus — and 1 related terms.
  • The strongest evidence on file: Phosphatidylserine is rated "Possibly Effective" for Age-related cognitive decline (Natural Medicines).
  • Also on file: Phosphatidylserine is rated "Possibly Effective" for Alzheimer disease.
  • Also on file: Phosphatidylserine is rated "Insufficient Reliable Evidence To Rate" for Cognitive function, Dementia.

Calcium carbonate is effective for kidney failure, indigestion, low blood calcium (hypocalcemia), high blood potassium (hyperkalemia), and osteoporosis — in fact, it's likely effective for bone health specifically. Phosphatidyl serine shows possibly effective evidence for age-related cognitive decline and Alzheimer disease.

For other uses listed in the research — athletic performance, ADHD, general cognitive function, and dementia — the evidence available to us is insufficient to rate whether it works.

The evidence, ingredient by ingredient Calcium Phosphatidylserine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium is generally well tolerated at recommended doses, though high amounts can cause problems. The most common side effects from oral calcium are belching, constipation, diarrhea, gas, and stomach upset.

Rarely, very high calcium doses have raised concerns about kidney stones and a condition called calciphylaxis. Additionally, some research suggests calcium intake above 1500–2000 mg per day may be linked to increased prostate cancer risk and possibly cardiovascular concerns, though these findings are debated.

Phosphatidyl serine is generally well tolerated in short-term studies, but long-term safety isn't fully established. Common side effects are flatulence, nausea, headache, and insomnia — particularly insomnia at higher doses (around 600 mg).

The safety data advises against using phosphatidyl serine in pregnancy and recommends avoiding it while breastfeeding. Calcium is considered likely safe in pregnancy at recommended amounts; adequate calcium is important during pregnancy and breastfeeding, but stay within suggested levels unless your doctor advises otherwise.

Side effects, ingredient by ingredient Calcium Phosphatidylserine

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Calcium, Phosphatidylserine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: heart-rhythm medications; lithium.
  • For scale: 387 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your doctor or pharmacist if you take HIV integrase inhibitors (dolutegravir, elvitegravir), the antibiotic ceftriaxone, levothyroxine for your thyroid, the heart rhythm drug sotalol, the blood-pressure medication diltiazem, calcipotriene for psoriasis, anticholinergic drugs, or cholinergic medications. Timing and dose adjustments may be necessary.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This product makes sense for someone who needs both bone support and brain-health support and has no conflicting medications — especially if you take integrase inhibitors for HIV, oral cephalosporin antibiotics, or thyroid medication. If you're on any heart, blood-pressure, bladder, or anticholinergic drugs, or if you use calcipotriene topically, check with your own doctor or pharmacist before starting, because spacing requirements or dose adjustments may be needed.

Women who are pregnant or breastfeeding should talk with their provider about the phosphatidyl serine component before using this product.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 22, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Phosphatidyl Serine 150 mg Soy-Free, straight from the product label.

Brand NOW
Barcode (UPC) 733739023896
Net contents 60 Veg Capsule(s)
Market status On market
Date entered into DSLD Jun 22, 2023
DSLD ID 292057
Product type Fat/fatty Acid
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Phosphatidyl Serine 150 mg Soy-Free by NOW, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Veg. Capsule(s)
Maximum serving Sizes:
1 Veg. Capsule(s)
Servings per container
60
UPC/BARCODE
733739023896
IngredientAmount% DV
Calcium40 mg3%
Calcium Carbonate147 mg--
Phosphatidyl Serine150 mg--

Other ingredients: Hypromellose, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide, Stearic Acid, Croscarmellose Sodium, Ascorbyl Palmitate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Suggested Usage: Take 1 capsule 1 to 2 times daily, preferably with food.

Formula

NOW Soy-Free Phosphatidyl Serine is a phospholipid compound derived from non-GMO sunflower lecithin. Phosphatidyl serine plays an essential role in cell membrane composition and intercellular communication. It is an especially important structural component of nerve cell membranes, where it assists in the conduction of electrical impulses and facilitates the activity of neurotransmitters involved in learning, memory, and mood.

Sharp PS Green

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Precautions

Caution: For adults only. Keep out of reach of children.

Consult physician if pregnant/nursing, taking medication, or have a medical condition.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

Formulation

Natural color variation may occur in this product.

Brain health

Vegetarian/Vegan

Made and quality tested in the USA with globally sourced ingredients.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients.

Storage

Store in a cool, dry place after opening.

Seals/Symbols

GMP Quality Assured

FDA Statement of Identity

A Dietary Supplement

General Statements

General Health Family owned since 1968.

Brand IP Statement(s)

Sharp PS is a registered trademark of Enzymotec Ltd.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Phosphatidyl Serine 150 mg Soy-Free by NOW label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Phosphatidyl Serine 150 mg Soy-Free label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Phosphatidyl Serine 150 mg Soy-Free by NOW

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Veg. Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Calcium

Interacts with
168 drugs
40 mg per serving

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Phosphatidyl Serine

Interacts with
219 drugs
150 mg per serving Form: Sunflower Lecithin

Phosphatidylserine is a natural fat-like compound found in cell membranes, especially in the brain, and it is sold mainly to support memory and thinki...

Phosphatidyl Serine monograph & interactions

Other (inactive) ingredients: Hypromellose, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide, Stearic Acid, Croscarmellose Sodium, Ascorbyl Palmitate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Phosphatidyl Serine 150 mg Soy-Free by NOW Drug Interactions

Want to check YOUR meds against Phosphatidyl Serine 150 mg Soy-Free?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
387Drugs
7 Major 362 Moderate 18 Minor

Ingredients driving the most interactions

Phosphatidyl Serine 219
Calcium 168

Individual Drug Interactions

The ingredients in Phosphatidyl Serine 150 mg Soy-Free interact with 387 drugs. Click any drug to see the details.

2 of the 2 ingredients in Phosphatidyl Serine 150 mg Soy-Free interact with drugs. Each result below shows which ingredient is responsible. Phosphatidyl Serine Calcium

Each ingredient & the kinds of drugs it affects

For each ingredient in Phosphatidyl Serine 150 mg Soy-Free with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Phosphatidyl Serine2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, phosphatidylserine might decrease the effectiveness anticholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically interfere with the activity of anticholinergic agents.

Likelihood Possible Evidence B
Cholinergic Drugs

Theoretically, phosphatidylserine might have additive effects with cholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically lead to additive cholinergic effects when used with cholinergic drugs.

Likelihood Possible Evidence B
Phosphatidyl Serine full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Phosphatidyl Serine 150 mg Soy-Free, from the product label.

NOW

See all NOW products
Name
NOW Foods
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

Phosphatidyl Serine 150 mg Soy-Free by NOW: Common Questions

Does Phosphatidyl Serine 150 mg Soy-Free by NOW interact with any medications?
Yes. Based on its ingredients, Phosphatidyl Serine 150 mg Soy-Free has a known interaction with 387 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Phosphatidyl Serine 150 mg Soy-Free contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm pregnant?
Calcium at recommended amounts is considered likely safe and actually important during pregnancy. However, phosphatidyl serine safety data advises against using it in pregnancy. Talk with your doctor or pharmacist — they can advise whether this product is right for you or if you should take just the calcium component separately.
Can I take this while breastfeeding?
Calcium is fine during breastfeeding at recommended amounts. Phosphatidyl serine safety while breastfeeding is unknown, so the data recommends avoiding it. Check with your provider to see if just the calcium part makes sense for you.
What side effects might I notice?
From the calcium, you might experience belching, constipation, diarrhea, gas, or stomach upset. From phosphatidyl serine, common ones are nausea, headache, gas, and insomnia — especially if you take a higher dose. Most people tolerate these ingredients well.
Does phosphatidyl serine really help with memory or Alzheimer disease?
Phosphatidyl serine shows possibly effective evidence for age-related cognitive decline and Alzheimer disease based on available research. For other cognitive uses like ADHD or general memory, the evidence we have isn't strong enough to rate. Talk with your doctor about whether it makes sense for your specific situation.
Why is this soy-free?
Phosphatidyl serine is often extracted from soy, so some people avoid it for allergy, sensitivity, or dietary reasons. This version uses a non-soy source instead.
Is there anything else in the capsule besides the two active ingredients?
Yes — there are several inactive ingredients (like microcrystalline cellulose and magnesium stearate) that help form and stabilize the capsule. These are standard binders and flow agents and aren't the active components.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Phosphatidyl Serine 150 mg Soy-Free label
Go deeper

The Full Monographs Behind Phosphatidyl Serine 150 mg Soy-Free’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

Phosphatidylserine

Interacts with 219 drugs

Phosphatidylserine is a natural fat-like compound found in cell membranes, especially in the brain, and it is sold mainly to support memory and thinking. Some research suggests possible bene...

Read the full Phosphatidylserine monograph →
Sources

Sources & How We Checked

Phosphatidyl Serine 150 mg Soy-Free's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 71 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Calcium 62 references
  1. Shils M, Olson A, Shike M. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994.
  2. Hernandez-Avila M, Gonzalez-Cossio T, Hernandez-Avila JE, et al. Dietary calcium supplements to lower blood lead levels in lactating women: a randomized placebo-controlled trial. Epidemiology 2003;14:206-12.. PubMed
  3. Thys-Jacobs S, Ceccarelli S, Bierman A, et al. Calcium supplementation in premenstrual syndrome: a randomized crossover trial. J Gen Intern Med 1989;4:183-9. PubMed
  4. Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
  5. Clemens JD, Feinstein AR. Calcium carbonate and constipation: a historical review of medical mythopoeia. Gastroenterology 1977;72:957-61. DOI
  6. Saunders D, Sillery J, Chapman R. Effect of calcium carbonate and aluminum hydroxide on human intestinal function. Dig Dis Sci 1988;33:409-13. PubMed
  7. Friedman PA, Bushinsky DA. Diuretic effects on calcium metabolism. Semin Nephrol 1999;19:551-6.
  8. Koo WK, Walters JC, Esterlitz J, et al. Maternal calcium supplementation and fetal bone mineralization. Obstet Gynecol 1999;94:577-82. DOI
  9. Raman L, Rajalakshmi K, Krishnamachari KAVR, et al. Effect of calcium supplementation to undernourished mothers during pregnancy on the bone density of the neonates. Am J Clin Nutr 1978; 31:466-9. DOI
  10. Murry JJ, Healy MD. Drug-mineral interactions: a new responsibility for the hospital dietician. J Am Diet Assoc 1991;91:66-73.
  11. Chan JM, Giovannucci E, Andersson SO, et al. Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer. Cancer Causes Control 1998;9:559-66.
  12. Butner LE, Fulco PP, Feldman G, et al. Calcium carbonate-induced hypothyroidism. Ann Intern Med 2000:132:595. PubMed
  13. Schneyer CR. Calcium carbonate and reduction of levothyroxine efficacy. JAMA 1998;279:750. PubMed
  14. Moser LR, Smythe MA, Tisdale JE. The use of calcium salts in the prevention and management of verapamil-induced hypotension. Ann Pharmacother 2000;34:622-9. PubMed
  15. Singh N, Singh PN, Hershman JM. Effect of calcium carbonate on the absorption of levothyroxine. JAMA 2000;283:2822-5. PubMed
  16. Kahela P, Anttila M, Tikkanen R, Sundquist H. Effect of food, food constituents and fluid volume on the bioavailability of sotalol. Acta Pharmacol Toxicol (Copenh) 1979;44:7-12.. PubMed
  17. Pletz MW, Petzold P, Allen A, et al. Effect of calcium carbonate on bioavailability of orally administered gemifloxacin. Antimicrob Agents Chemother 2003;47:2158-60.. PubMed
  18. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  19. Decktor DL, Robinson M, Maton PN, et al. Effects of aluminum/magnesium hydroxide and calcium carbonate on esophageal and gastric pH in subjects with heartburn. Am J Ther 1995;2:546-52. PubMed
  20. Simoneau G. Absence of rebound effect with calcium carbonate. Eur J Drug Metab Pharmacokinet 1996;21:351-7. PubMed
  21. Peters ML, Leonard M, Licata AA. Role of alendronate and risedronate in preventing and treating osteoporosis. Cleve Clin J Med 2001;68:945-51. PubMed
  22. Bourke JF, Mumford R, Whittaker P, et al. The effects of topical calcipotriol on systemic calcium homeostasis in patients with chronic plaque psoriasis. J Am Acad Dermatol 1997;37:929-34.
  23. Gueguen L, Pointillart A. The bioavailability of dietary calcium. J Am Coll Nutr 2000;19:119s-136s. PubMed
  24. Vella A, Gerber TC, Hayes DL, Reeder GS. Digoxin, hypercalcaemia, and cardiac conduction. Postgrad Med J 1999;75:554-6. PubMed
  25. Bania TC, Blaufeux B, Hughes S, et al. Calcium and digoxin vs. calcium alone for severe verapamil toxicity. Acad Emerg Med 2000;7:1089-96. PubMed
  26. Tseng M, Breslow RA, Graubard BI, Ziegler RG. Dairy, calcium, and vitamin D intakes and prostate cancer risk in the National Health and Nutrition Examination Epidemiologic Follow-up Study cohort. Am J Clin Nutr 2005;81:1147-54. PubMed
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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