Major interaction on record — check this product against your medications before combining. Based on 4 of 7 ingredients. Check your meds →
Dietary supplement

Passifen (Passiflora) Ingredients & Drug Interactions

by Douglas Laboratories

Passifen (Passiflora) label
See full label image
Liquid Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Passifen (Passiflora) 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

Passifen (Passiflora) is a dietary supplement by Douglas Laboratories with 7 active ingredients. Its ingredients are commonly taken for anxiety and stress, trouble sleeping, restlessness.Based on those ingredients, 1,290 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Passiflora Inc, Coffee Cruda, Magnesia Phosphorica. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Passifen (Passiflora) by Douglas Laboratories

Ask about any prescription or over-the-counter medication and we check it for interactions with Passifen (Passiflora) by Douglas Laboratories — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Passifen (Passiflora) by Douglas Laboratories

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 7 of its 7 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Passifen contains 7 ingredients, of which the active ones are passion flower (used for sleep and anxiety), coffee cruda (which provides caffeine for mental alertness), magnesia phosphorica (a magnesium compound), and ignatius amara (ignatius bean). The product also contains three other ingredients — palladium, tellurium, and phosphoric acid — that we have no data on.

There are no inactive fillers or binders listed.

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: Support relaxation and sleep.
  • We looked for evidence on: Insomnia, Adjustment disorders, Benzodiazepine withdrawal, Depression, nervousness, restlessness — and 1 related terms.
  • The strongest evidence on file: Passion Flower is rated "Possibly Effective" for Insomnia (Natural Medicines).
  • Also on file: Passion Flower is rated "Insufficient Reliable Evidence To Rate" for Adjustment disorders, Benzodiazepine withdrawal.
  • Also on file: Coffee is rated "Insufficient Reliable Evidence To Rate" for Depression.

Passion flower in this product is rated possibly effective for insomnia and pre-procedural anxiety, though the evidence is not definitive. For ADHD and benzodiazepine withdrawal, the data is insufficient to rate it.

The coffee cruda ingredient is likely effective for mental alertness and possibly effective for Parkinson disease, heart failure, diabetes, and overall mortality. Magnesia phosphorica (magnesium) is effective for indigestion, constipation, low magnesium levels, and prevention of pre-eclampsia in pregnancy.

Ignatius bean has no established effectiveness ratings in our data.

The evidence, ingredient by ingredient Passion Flower Ignatius Bean Coffee Magnesium

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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Passion flower is generally well tolerated but commonly causes drowsiness, dizziness, and confusion. It is not safe in pregnancy due to lack of safety data and possible effects on the uterus, and breastfeeding safety data is insufficient — avoid while nursing.

Ignatius bean is considered unsafe; it contains strychnine and brucine, toxic compounds that cause severe muscle spasms, seizures, and at high doses can be fatal. Coffee cruda (caffeine) is generally safe in moderate amounts for healthy adults but can cause agitation, anxiety, insomnia, and heart palpitations, especially at higher intakes.

In pregnancy, limit caffeine and discuss safe amounts with your doctor; caffeine passes into breast milk, so keep intake low and watch for fussiness or sleep problems in your baby. Magnesia phosphorica (magnesium) is generally well tolerated but may cause diarrhea, nausea, and gastrointestinal irritation at oral doses.

Side effects, ingredient by ingredient Passion Flower Ignatius Bean Coffee Magnesium

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?
  • 3 of the 4 matched ingredients can interact with medications — Passion Flower, Coffee, Magnesium.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 1,291 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, check with your doctor or pharmacist if you take any of the following: ephedrine (life-threatening risk), sedative or anti-anxiety medications, blood pressure or heart medications (calcium channel blockers), diabetes medications (sulfonylureas), seizure medications (lamotrigine), antipsychotics (clozapine), muscle relaxants, antibiotics (quinolones), bone medications (bisphosphonates), acid-reducing medications, or medications for Parkinson disease (levodopa/carbidopa). No interactions are documented for the three ingredients we could not check.

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 combines passion flower for sleep and anxiety support, caffeine for mental alertness, magnesium for digestive support, and ignatius bean — though the bean's toxicity raises safety concerns. If you take any sedative medication, blood pressure drug, diabetes medication, antibiotic, or any of the other 1,291+ drugs affected by these ingredients, you'll want to check them against this product before starting.

Talk with your doctor or pharmacist before taking Passifen, especially if you're pregnant, breastfeeding, or taking any regular prescription medications.

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

Assessment coverage: 4 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2012.

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 Passifen (Passiflora), straight from the product label.

Brand Douglas Laboratories
Barcode (UPC) 310539011409
Net contents 30 mL
Market status On market
Date entered into DSLD Jun 25, 2012
DSLD ID 8171
Product type Other Combinations
Supplement form Liquid
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years)
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 Passifen (Passiflora) by Douglas Laboratories, 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 mL
Maximum serving Sizes:
1 mL
Servings per container
30
UPC/BARCODE
310539011409
IngredientAmount% DV
Palladium6 C--
Tellurium6 C--
Phosphoric Acid7 C--
Passiflora Inc3 X--
Ignatia Amara4 C--
Coffee Cruda5 C--
Magnesia Phosphorica6 C--

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.
FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Usage: As a dietary supplement, adults take 10 drops in a small amount of water 3 times daily or as directed by your healthcare professional.

Indications: Insomnia and nervousness.

Precautions

If pregnant or nursing, seek professional advice before using.

KEEP OUT OF REACH OF CHILDREN.

Tamper resistant package, do not use if seal around cap is broken or missing.

Storage

For optimal storage conditions, store in a cool, dry place. DO NOT FREEZE.

General

Formula #7167

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

See for yourself

Passifen (Passiflora) by Douglas Laboratories label

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

Passifen (Passiflora) 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 Passifen (Passiflora) by Douglas Laboratories

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container30 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.

Palladium

6 C per serving

Tellurium

6 C per serving

Phosphoric Acid

7 C per serving

Passiflora Inc

Interacts with
836 drugs
3 X per serving

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restless...

Passiflora Inc monograph & interactions

Ignatia Amara

No known
interactions
4 C per serving

Ignatius bean is a seed that naturally contains strychnine and brucine, which are highly toxic poisons. The raw seed or crude extracts should never be...

Ignatia Amara monograph & interactions

Coffee Cruda

Interacts with
591 drugs
5 C per serving

Coffee is a widely consumed beverage made from roasted coffee beans, valued mainly for its caffeine, which boosts alertness and energy. For most healt...

Coffee Cruda monograph & interactions

Magnesia Phosphorica

Interacts with
295 drugs
6 C per serving

Magnesium is an essential mineral your body needs for muscles, nerves, blood pressure, and many other functions, and supplements are useful for preven...

Magnesia Phosphorica monograph & interactions
Interaction report

Passifen (Passiflora) by Douglas Laboratories Drug Interactions

Want to check YOUR meds against Passifen (Passiflora)?

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
1,290Drugs
14 Major 785 Moderate 491 Minor

Ingredients driving the most interactions

Passiflora Inc 836
Coffee Cruda 591
Magnesia Phosphorica 295

Individual Drug Interactions

The ingredients in Passifen (Passiflora) interact with 1,290 drugs. Click any drug to see the details.

3 of the 7 ingredients in Passifen (Passiflora) interact with drugs. Each result below shows which ingredient is responsible. Passiflora Inc Coffee Cruda Magnesia Phosphorica

Each ingredient & the kinds of drugs it affects

For each ingredient in Passifen (Passiflora) 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.

Passiflora Inc3 drug types · 836 drugs

Cns Depressants

Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.
Research in animals and humans shows that passion flower has sedative effects which can be additive when used with sedative medications like lorazepam.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, passion flower might decrease the effects of CYP3A4 substrates.
In vitro research suggests that passion flower can induce CYP3A4 enzymes, albeit to a much lower degree than rifampin, a known CYP3A4 inducer.

Likelihood Possible Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, passion flower might reduce the bioavailability of OATP2B1 and OATP1A2 substrates.
In vitro research shows that the passion flower constituents apigenin and vitexin inhibit OATP2B1 and OATP1A2. This inhibition may be dose-dependent. One specific high-flavonoid passion flower extract (Valverde) seems to inhibit OATP2B1 and OATP1A2, while another extract with a lower flavonoid concentration (Arkocaps) shows less potent inhibition. OATPs are responsible for the uptake of drugs and other compounds into the body; however, the specific activities of OATP2B1 and OATP1A2 are not well characterized.

Likelihood Possible Evidence D
Passiflora Inc full monograph & interactions

Coffee Cruda33 drug types · 591 drugs

Ephedrine

Theoretically, concomitant use might increase the risk of stimulant adverse effects.
Coffee contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death. Tell patients to avoid taking caffeine with ephedrine and other stimulants.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, coffee might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Coffee contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products, be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Alendronate (Fosamax)

Coffee reduces alendronate bioavailability.
Separate coffee ingestion and alendronate administration by two hours. Coffee reduces alendronate bioavailability by 60%.

Likelihood Probable Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, coffee may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Coffee contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, the caffeine in coffee might increase the risk of bleeding when used concomitantly with these agents. However, this interaction has not been reported in humans. There is some evidence that caffeinated coffee might increase the fibrinolytic activity in blood.

Likelihood Unlikely Evidence D
Beta-Adrenergic Agonists

Theoretically, concomitant use of large amounts of coffee might increase cardiac inotropic effects of beta-agonists.
Coffee contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Cimetidine (Tagamet)

Theoretically, cimetidine might increase the effects and adverse effects of caffeine in coffee.
Coffee contains caffeine. Cimetidine can reduce caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, coffee might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Coffee contains caffeine. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in coffee.
Coffee contains caffeine. Oral contraceptive drugs can decrease caffeine clearance by 40% to 65%.

Likelihood Probable Evidence B
Dipyridamole (Persantine)

Theoretically, coffee might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Coffee contains caffeine. Caffeine is a methylxyanthine that may inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products such as coffee, be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
Coffee contains caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, concomitant use might increase the risk of hypokalemia.
Coffee contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Coffee contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Coffee contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence B
Lamotrigine (Lamictal)

Coffee consumption can decrease the levels and clinical effects of lamotrigine.
A pharmacokinetic study in patients taking lamotrigine shows that consumption of coffee, both caffeinated and decaffeinated, can decrease the area under the concentration-time curve (AUC) and the peak plasma level (Cmax) of lamotrigine. Each additional cup of coffee reduced the AUC and Cmax by 4% and 3%, respectively. It is unclear whether this interaction is due to induction of lamotrigine metabolism or inhibition of lamotrigine absorption.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Coffee can reduce the absorption of levothyroxine.
In some patients, coffee can reduce levothyroxine absorption, possibly through the formation of non-absorbable complexes. A pharmacokinetic study in these patients found that 25-30 mL of espresso coffee consumed with levothyroxine tablets delayed the time to peak plasma levels by 38-43 minutes, reduced the peak plasma level (Cmax) by 19% to 36%, and reduced the area under the curve (AUC) by 27% to 36%. Coffee consumed one hour after levothyroxine did not affect absorption. It is not known whether this interaction occurs with other types of coffee. Tell patients to avoid drinking coffee at the same time that they take their levothyroxine, and for up to an hour afterwards.

Likelihood Possible Evidence B
Lithium

Theoretically, abrupt coffee withdrawal might increase the levels and adverse effects of lithium.
Coffee contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels. Two cases of lithium tremor that worsened with abrupt coffee withdrawal have been reported. There is also one case of a 2.8-fold increase in blood lithium levels after a patient taking lithium reduced his coffee consumption from 13-20 cups daily to 10 cups daily.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Coffee contains caffeine. Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patient switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Coffee contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, coffee might reduce the effects of pentobarbital.
Coffee contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Coffee contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Pioglitazone (Actos)

Theoretically, coffee might increase the levels and clinical effects of pioglitazone.
Coffee contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Coffee contains caffeine. Concomitant use of caffeine and quinolones can decrease caffeine clearance and increase effects and risk of adverse effects.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Coffee contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce metabolism of one or both agents.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, concomitant use might increase stimulant adverse effects.
Coffee contains caffeine. Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of adverse effects.

Likelihood Probable Evidence C
Theophylline

Theoretically, coffee might increase the levels and adverse effects of theophylline.
Coffee contains caffeine, which can increase theophylline levels.

Likelihood Probable Evidence B
Coffee Cruda full monograph & all 33 interactions

Magnesia Phosphorica15 drug types · 295 drugs

Levodopa/Carbidopa (Sinemet)

Magnesium can reduce the bioavailability of levodopa/carbidopa.
Clinical research in healthy volunteers shows that taking magnesium oxide 1000 mg with levodopa 100 mg/carbidopa 10 mg reduces the area under the curve (AUC) of levodopa by 35% and of carbidopa by 81%. In vitro and animal research shows that magnesium produces an alkaline environment in the digestive tract, which might lead to degradation and reduced bioavailability of levodopa/carbidopa.

Likelihood Probable Evidence B
Aminoglycoside Antibiotics

Concomitant use of aminoglycoside antibiotics and magnesium can increase the risk for neuromuscular weakness.
Both aminoglycosides and magnesium reduce presynaptic acetylcholine release, which can lead to neuromuscular blockade and possible paralysis. This is most likely to occur with high doses of magnesium given intravenously.

Likelihood Possible Evidence D
Antacids

Use of acid reducers may reduce the laxative effect of magnesium oxide.
A retrospective analysis shows that, in the presence of H2 receptor antagonists (H2RAs) or proton pump inhibitors (PPIs), a higher dose of magnesium oxide is needed for a laxative effect. This may also occur with antacids. Under acidic conditions, magnesium oxide is converted to magnesium chloride and then to magnesium bicarbonate, which has an osmotic laxative effect. By reducing acidity, antacids may reduce the conversion of magnesium oxide to the active bicarbonate salt.

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

Magnesium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide should be taken at least 2 hours before or 6 hours after magnesium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Magnesium can decrease absorption of bisphosphonates.
Cations, including magnesium, can decrease bisphosphonate absorption. Advise patients to separate doses of magnesium and these drugs by at least 2 hours.

Likelihood Probable Evidence B
Calcium Channel Blockers

Magnesium can have additive effects with calcium channel blockers, although evidence is conflicting.
Magnesium inhibits calcium entry into smooth muscle cells and may therefore have additive effects with calcium channel blockers. Severe hypotension and neuromuscular blockades may occur when nifedipine is used with intravenous magnesium, although some contradictory evidence suggests that concurrent use of magnesium with nifedipine does not increase the risk of neuromuscular weakness. High doses of magnesium could theoretically have additive effects with other calcium channel blockers.

Likelihood Possible Evidence D
Digoxin

Magnesium salts may reduce absorption of digoxin.
Clinical evidence suggests that treatment with oral magnesium hydroxide or magnesium trisilicate reduces absorption of digoxin from the intestines. This may reduce the blood levels of digoxin and decrease its therapeutic effects.

Likelihood Possible Evidence B
Potassium-Sparing Diuretics

Potassium-sparing diuretics decrease excretion of magnesium, possibly increasing magnesium levels.
Potassium-sparing diuretics also have magnesium-sparing properties, which can counteract the magnesium losses associated with loop and thiazide diuretics. Theoretically, increased magnesium levels could result from concomitant use of potassium-sparing diuretics and magnesium supplements.

Likelihood Probable Evidence D
Quinolone Antibiotics

Magnesium decreases absorption of quinolones.
Magnesium can form insoluble complexes with quinolones and decrease their absorption. Advise patients to take these drugs at least 2 hours before, or 4 to 6 hours after, magnesium supplements.

Likelihood Probable Evidence D
Skeletal Muscle Relaxants

Parenteral magnesium alters the pharmacokinetics of skeletal muscle relaxants, increasing their effects and accelerating the onset of effect.
Parenteral magnesium shortens the time to onset of skeletal muscle relaxants by about 1 minute and prolongs the duration of action by about 2 minutes. Magnesium potentiates the effects of skeletal muscle relaxants by decreasing calcium-mediated release of acetylcholine from presynaptic nerve terminals, reducing postsynaptic sensitivity to acetylcholine, and having a direct effect on the membrane potential of myocytes. Magnesium also has vasodilatory actions and increases cardiac output, allowing a greater amount of muscle relaxant to reach the motor end plate. A clinical study found that low-dose rocuronium (0.45 mg/kg), when given after administration of magnesium 30 mg/kg over 10 minutes, has an accelerated onset of effect, which matches the onset of effect seen with a full-dose rocuronium regimen (0.6 mg/kg). In another clinical study, onset times for rocuronium doses of 0.3, 0.6, and 1.2 mg/kg were 86, 76, and 50 seconds, respectively, when given alone, but were reduced to 66, 44, and 38 seconds, respectively, when the doses were given after a 15-minute infusion of magnesium sulfate 60 mg/kg. Giving intraoperative intravenous magnesium sulfate, 50 mg/kg loading dose followed by 15 mg/kg/hour, reduces the onset time of rocuronium, enhances its clinical effects, reduces the dose of intraoperative opiates, and prolongs the spontaneous recovery time. It does not affect the activity of subsequently administered neostigmine.

Likelihood Probable Evidence A
Sulfonylureas

Magnesium increases the systemic absorption of sulfonylureas, increasing their effects and side effects.
Clinical research shows that administration of magnesium hydroxide with glyburide increases glyburide absorption, increases maximal insulin response by 35-fold, and increases the risk of hypoglycemia, when compared with glyburide alone. A similar interaction occurs between magnesium hydroxide and glipizide. The mechanism of this effect appears to be related to the elevation of gastrointestinal pH by magnesium-based antacids, increasing solubility and enhancing absorption of sulfonylureas.

Likelihood Probable Evidence B
Tetracycline Antibiotics

Magnesium decreases absorption of tetracyclines.
Magnesium can form insoluble complexes with tetracyclines in the gut and decrease their absorption and antibacterial activity. Advise patients to take these drugs 1 hour before or 2 hours after magnesium supplements.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, magnesium may have antiplatelet effects, but the evidence is conflicting.
In vitro evidence shows that magnesium sulfate inhibits platelet aggregation, even at low concentrations. Some preliminary clinical evidence shows that infusion of magnesium sulfate increases bleeding time by 48% and reduces platelet activity. However, other clinical research shows that magnesium does not affect platelet aggregation, although inhibition of platelet-dependent thrombosis can occur.

Likelihood Unlikely Evidence B
Gabapentin (Neurontin)

Gabapentin absorption can be decreased by magnesium.
Clinical research shows that giving magnesium oxide orally along with gabapentin decreases the maximum plasma concentration of gabapentin by 33%, time to maximum concentration by 36%, and area under the curve by 43%. Advise patients to take gabapentin at least 2 hours before, or 4 to 6 hours after, magnesium supplements.

Likelihood Unlikely Evidence B
Sevelamer (Renagel, Renvela)

Sevelamer may increase serum magnesium levels.
In patients on hemodialysis, sevelamer use was associated with a 0.28 mg/dL increase in serum magnesium. The mechanism of this interaction remains unclear.

Likelihood Possible Evidence B
Magnesia Phosphorica full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Passifen (Passiflora), from the product label.

Douglas Laboratories

See all Douglas Laboratories products
Name
Douglas Laboratories
Street Address
600 Boyce Road
City
Pittsburgh
State
PA
ZipCode
15205
Web Address
www.douglaslabs.com
Pharmacist Counseling Corner

Passifen (Passiflora) by Douglas Laboratories: Common Questions

Does Passifen (Passiflora) by Douglas Laboratories interact with any medications?
Yes. Based on its ingredients, Passifen (Passiflora) has a known interaction with 1,290 medications, including 14 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Passifen (Passiflora) contains 7 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.
Is Passifen safe to take if I'm pregnant?
Passion flower in this product is not safe during pregnancy — there's a lack of safety data and possible effects on the uterus. Coffee cruda (caffeine) is possibly unsafe; the safety data advises limiting it and discussing safe amounts with your doctor. Magnesia phosphorica (magnesium) may be needed in pregnancy, but use only under your doctor's guidance. Ignatius bean is unsafe in pregnancy. Talk with your doctor before taking this product if you're pregnant.
Can I take Passifen while breastfeeding?
Passion flower safety data is insufficient for breastfeeding — it's best avoided. Coffee cruda (caffeine) is possibly safe but passes into breast milk; keep intake low and watch your baby for fussiness or sleep problems. Magnesia phosphorica (magnesium) safety data is insufficient for supplements — normal dietary amounts are appropriate, but check with your doctor. Ignatius bean is unsafe while breastfeeding. Discuss this product with your doctor or pharmacist before taking it.
Will Passifen make me drowsy?
Yes — drowsiness is a common side effect of passion flower, along with dizziness and confusion. The coffee cruda (caffeine) ingredient may partly counteract this, but you should avoid driving or operating machinery until you know how this product affects you. If you also take sedative medications, the drowsiness risk is higher.
What is ignatius bean and is it safe?
Ignatius bean (ignatius amara) is in this product, but it is not safe — it contains strychnine and brucine, toxic compounds. Even small doses can cause restlessness, anxiety, muscle twitching, and spasms; larger doses can cause seizures and death. Because of this toxicity, the safety data advises against use. This ingredient raises a serious safety concern about this product.
Does this product really have caffeine in it?
Yes — the coffee cruda ingredient is a caffeine source. Caffeine can increase mental alertness and is likely effective for that purpose, but it can also cause agitation, anxiety, insomnia, and heart palpitations, especially at higher doses or in sensitive people. It also interacts with many medications, so check with your doctor if you take any regular prescriptions.
What is magnesium phosphorica used for in this product?
Magnesia phosphorica (magnesium) is effective for indigestion and constipation. It is also effective for correcting low magnesium levels and preventing pre-eclampsia in pregnancy. However, it can interact with many medications and may cause diarrhea or nausea at oral doses.

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

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Passifen (Passiflora) label
Go deeper

The Full Monographs Behind Passifen (Passiflora)’s Ingredients

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

Herb & supplement monograph

Passion Flower

Interacts with 836 drugs

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restlessness, but the evidence is limited and mo...

Read the full Passion Flower monograph → Herb & supplement monograph

Ignatius Bean

Ignatius bean is a seed that naturally contains strychnine and brucine, which are highly toxic poisons. The raw seed or crude extracts should never be taken because even small amounts can ca...

Read the full Ignatius Bean monograph → Herb & supplement monograph

Coffee

Interacts with 591 drugs

Coffee is a widely consumed beverage made from roasted coffee beans, valued mainly for its caffeine, which boosts alertness and energy. For most healthy adults, moderate coffee intake is gen...

Read the full Coffee monograph → Herb & supplement monograph

Magnesium

Interacts with 295 drugs

Magnesium is an essential mineral your body needs for muscles, nerves, blood pressure, and many other functions, and supplements are useful for preventing or correcting deficiency. Some othe...

Read the full Magnesium monograph →
Sources

Sources & How We Checked

Passifen (Passiflora)'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 282 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.

Passion Flower 19 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  3. Fisher AA, Purcell P, Le Couteur DG. Toxicity of Passiflora incarnata L. J Toxicol Clin Toxicol 2000;38:63-6.
  4. Akhondzadeh S, Naghavi HR, Shayeganpour A, et al. Passionflower in the treatment of generalized anxiety: a pilot double-blind randomized controlled trial with oxazepam. J Clin Pharm Ther 2001;26:363-7. PubMed
  5. Farnsworth N, Bingel A, Cordell G, et al. Potential value of plants as sources of new antifertility agents I. J Pharm Sci 1975;64:535-98. DOI
  6. Mori A, Hasegawa K, Murasaki M, et al. Clinical evaluation of Passiflamin (passiflora extract) on neurosis - multicenter double blind study in comparison with mexazolam. Rinsho Hyoka (Clinical Evaluation) 1993;21:383-440.
  7. Miyasaka LS, Atallah AN, Soares BG. Passiflora for anxiety disorder. Cochrane Database Syst Rev 2007;(1):CD004518. DOI
  8. Speroni E., Minghetti A. Neuropharmacological activity of extracts from Passiflora incarnata. Planta Med. 1988;54:488-91.
  9. Capasso A., Sorrentino L. Pharmacological studies on the sedative and hypnotic effect of Kava kava and Passiflora extracts combination. Phytomedicine. 2005;12:39-45. PubMed
  10. Carrasco MC, Vallejo JR, Pardo-de-Santayana M, et al. Interactions of Valeriana officinalis L. and Passiflora incarnata L. in a patient treated with lorazepam. Phytother Res. 2009 Dec;23:1795-6.
  11. Smith, G. W., Chalmers, T. M., and Nuki, G. Vasculitis associated with herbal preparation containing Passiflora extract. Br J Rheumatol. 1993;32(1):87-88.
  12. Soulimani, R., Younos, C., Jarmouni, S., Bousta, D., Misslin, R., and Mortier, F. Behavioural effects of Passiflora incarnata L. and its indole alkaloid and flavonoid derivatives and maltol in the mouse. J Ethnopharmacol. 1997;57(1):11-20. PubMed
  13. Nojoumi M, Ghaeli P, Salimi S, Sharifi A, Raisi F. Effects of Passion Flower Extract, as an Add-On Treatment to Sertraline, on Reaction Time in Patients ?with Generalized Anxiety Disorder: A Double-Blind Placebo-Controlled Study. Iran J Psychiatry. 2016;1
  14. Rokhtabnak F, Ghodraty MR, Kholdebarin A, et al. Comparing the Effect of Preoperative Administration of Melatonin and Passiflora incarnata on Postoperative Cognitive Disorders in Adult Patients Undergoing Elective Surgery. Anesth Pain Med. 2016;7(1):e4123 PubMed
  15. Dantas LP, de Oliveira-Ribeiro A, de Almeida-Souza LM, Groppo FC. Effects of passiflora incarnata and midazolam for control of anxiety in patients undergoing dental extraction. Med Oral Patol Oral Cir Bucal. 2017;22(1):e95-e101. PubMed
  16. Ozturk Z, Kalayci CC. Pregnancy outcomes in psychiatric patients treated with passiflora incarnata. Complement Ther Med. 2018 Feb;36:30-32. PubMed
  17. da Cunha RS, Amorim KS, Gercina AC, et al. Herbal medicines as anxiolytics prior to third molar surgical extraction. A randomized controlled clinical trial. Clin Oral Investig. 2020. PubMed
  18. Schäfer AM, Gilgen PM, Spirgi C, et al. Constituents of Passiflora incarnata, but Not of Valeriana officinalis, Interact with the Organic Anion Transporting Polypeptides (OATP)2B1 and OATP1A2. Planta Med. 2021. PubMed
  19. Mazzari ALDA, Lacerda MG, Milton FA, et al. In vitro effects of European and Latin-American medicinal plants in CYP3A4 gene expression, glutathione levels, and P-glycoprotein activity. Front Pharmacol 2022;13:826395. PubMed

See these in context on the Passion Flower monograph →

Ignatius Bean 6 references
  1. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  4. Hardman J, Limbird L. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  5. Ellenhorn M. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. Baltimore, MD: Williams & Wilkins, 1997.
  6. Gruenwald J. PDR for Herbal Medicines. 1st ed ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

See these in context on the Ignatius Bean monograph →

Coffee 175 references
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  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  7. Lasswell WL Jr, Weber SS, Wilkins JM. In vitro interaction of neuroleptics and tricylic antidepressants with coffee, tea, and gallotannic acid. J Pharm Sci 1984;73:1056-8. PubMed
  8. Kulhanek F, Linde OK, Meisenberg G. Precipitation of antipsychotic drugs in interaction with coffee or tea. Lancet 1979;2:1130.
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  11. Grubben MJ, Boers GH, Blom HJ, et al. Unfiltered coffee increases plasma homocysteine concentrations in healthy volunteers: a randomized trial. Am J Clin Nutr 2000;71:480-4. PubMed
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See these in context on the Coffee monograph →

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See these in context on the Magnesium monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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