Interactions on record — worth a quick check against your medications. Based on 5 of 9 ingredients. Check your meds →
Dietary supplement

L-Arginine Caffeine-Free Ingredients & Drug Interactions

by SNAP

L-Arginine Caffeine-Free label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-Arginine Caffeine-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: Moderate

L-Arginine Caffeine-Free is a dietary supplement by SNAP with 9 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis, correcting vitamin d deficiency, immune system support.Based on those ingredients, 1,249 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Bioperine, Vitamin D3, L-Arginine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against L-Arginine Caffeine-Free by SNAP

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Arginine Caffeine-Free by SNAP — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of L-Arginine Caffeine-Free by SNAP

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 Aug 13, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 9 active ingredients.
  • “Snap Power Blend” is a proprietary blend — the label gives one combined amount (960 mg) without saying how much of each component you get.

SNAP L-Arginine Caffeine-Free contains 9 ingredients, of which the active ones are L-arginine, L-arginine hydrochloride, L-arginine alpha-ketoglutarate, L-citrulline, vitamin D3, Bioperine (black pepper extract), pine bark extract, Nitrosigine, and AstraGin. The L-arginine compounds work together to boost nitric oxide and support blood vessel function.

L-citrulline is converted by your body into L-arginine, extending its effects. Vitamin D3 supports bone health and immune function.

Bioperine enhances absorption of the other ingredients. Pine bark extract adds antioxidant support.

The capsule also contains inactive ingredients: hydroxypropyl methylcellulose, silica, and magnesium stearate.

Does it work?

Strong 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

This product doesn't appear to be marketed for a specific use, so we graded its ingredients' overall clinical evidence instead.

Strong

Strong clinical evidence supports its ingredients for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredients' overall clinical evidence instead.
  • On file: Familial hypophosphatemia — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Osteomalacia — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Renal osteodystrophy — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Rickets — rated "Effective" (Vitamin D) (Natural Medicines).
  • On file: Hypoparathyroidism — rated "Effective" (Vitamin D) (Natural Medicines).

The evidence for this product's active ingredients varies. L-citrulline has possibly effective evidence for athletic performance but possibly ineffective evidence for sarcopenia; the evidence isn't established for cardiovascular disease, heart failure, Reye syndrome, and diabetes.

Vitamin D3 is effective for familial hypophosphatemia, osteomalacia, renal osteodystrophy, rickets, and hypoparathyroidism. Pine bark extract is possibly effective for osteoarthritis and chronic venous insufficiency, and possibly effective for asthma, but possibly ineffective for high cholesterol.

We hold no effectiveness ratings for L-arginine by itself, Bioperine, Nitrosigine, or AstraGin.

The evidence, ingredient by ingredient Vitamin D L-arginine L-citrulline Black Pepper Maritime Pine

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-arginine and its variants are generally well tolerated short-term, but safety for self-treatment is not well established and it can lower blood pressure—use only under medical supervision. Most common side effects include abdominal pain, bloating, nausea, diarrhea, headache, insomnia, and flushing.

L-citrulline is generally well tolerated in healthy adults, though long-term safety isn't fully studied; gastrointestinal discomfort and heartburn are the most common effects. Vitamin D3 is generally safe at recommended doses but can cause toxicity at very high doses over time, with symptoms of high blood calcium levels.

Bioperine is generally safe as a food spice; at supplement strength, burning aftertaste, indigestion, and reduced taste perception are common, and allergic reactions are rare. Pine bark extract is generally well tolerated; gastrointestinal complaints, dizziness, and vertigo are most common, though a few rare cases of chest pain and heart failure worsening have been reported in patients with prior heart disease.

Side effects, ingredient by ingredient Vitamin D L-arginine L-citrulline Black Pepper Maritime Pine

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 5 of the 5 matched ingredients can interact with medications — Black Pepper, L-arginine, Vitamin D, Maritime Pine, L-citrulline.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 1,250 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 blood pressure medications (especially ACE inhibitors and ARBs), blood thinners or antiplatelet drugs, potassium-sparing diuretics, diabetes medications, heart rhythm drugs like digoxin or verapamil, phenytoin, atorvastatin, theophylline, rifampin, nevirapine, propranolol, or immunosuppressants. These are the medication types most affected by the ingredients we checked.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with strong clinical evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

SNAP L-Arginine Caffeine-Free is aimed at people looking to boost athletic performance and support circulation through L-arginine and supporting nutrients. If you take blood pressure medications, blood thinners, diabetes drugs, heart medications, or any other prescription, check your exact medications with the tool on this page before starting.

Pregnancy safety data for L-citrulline and pine bark extract advise against use; L-arginine is possibly safe and vitamin D3 is likely safe, but talk with your doctor or pharmacist about what's right for you before beginning.

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

Assessment coverage: 7 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 25, 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 L-Arginine Caffeine-Free, straight from the product label.

Brand SNAP
Barcode (UPC) 0643530160839
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Sep 25, 2023
DSLD ID 296759
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
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 L-Arginine Caffeine-Free by SNAP, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
0643530160839
IngredientAmount% DV
L-Arginine0 NP--
L-Citrulline0 NP--
Vitamin D310 mcg50%
L-Arginine Hydrochloride0 NP--
Bioperine0 NP--
Pine Bark Extract0 NP--
Nitrosigine0 NP--
L-Arginine Alpha-Ketoglutarate0 NP--
Snap Power Blend960 mg--
AstraGin0 NP--

Other ingredients: Hydroxypropyl Methylcellulose, Silica, Magnesium Stearate

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 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.

Brand IP Statement(s)

SNAP Supplements Simple Power of Nature Nitrosigine Nitrosigine, including the Nitrosigine logo, is patent protected and a registered trademark of Nutrition 21, LLC. BioPerine Bioperine is a registered trademark of Sabinsa Corporation.

Suggested/Recommended/Usage/Directions

Recommendations: As a dietary supplement, take 2 capsules with food daily or as directed by your medical provider.

Storage

Store away from humidity, heat, and light. Do not refrigerate.

Precautions

If any reactions occur, discontinue use of dietary supplement and consult your doctor. Warning: Do not exceed daily dosage. You should not take this product with alcohol.

This product should only be taken by healthy individuals at least 18 years of age or older. Keep out of reach of children.

Consult your healthcare provider if you are pregnant or nursing, or have any other medical concerns.

Formulation

Manufactured in a FDA registered facility Manufactured in a GMP certified facility Manufactured in USA

Power complex Physical performance Improved blood flow Muscle volume

Seals/Symbols

Manufactured in USA

FDA Statement of Identity

Dietary Supplement

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

See for yourself

L-Arginine Caffeine-Free by SNAP label

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

L-Arginine Caffeine-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 L-Arginine Caffeine-Free by SNAP

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule 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.

Vitamin D3

Interacts with
715 drugs
10 mcg per serving Form: Cholecalciferol

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D3 monograph & interactions

Snap Power Blend

960 mg per serving

Other (inactive) ingredients: Hydroxypropyl Methylcellulose, Silica, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Arginine Caffeine-Free by SNAP Drug Interactions

Want to check YOUR meds against L-Arginine Caffeine-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
1,249Drugs
1,203 Moderate 46 Minor

Ingredients driving the most interactions

Bioperine 1,019
Vitamin D3 715
L-Arginine 403
Pine Bark Extract 327
L-Citrulline 178

Individual Drug Interactions

The ingredients in L-Arginine Caffeine-Free interact with 1,249 drugs. Click any drug to see the details.

5 of the 9 ingredients in L-Arginine Caffeine-Free interact with drugs. Each result below shows which ingredient is responsible. Bioperine Vitamin D3 L-Arginine Pine Bark Extract L-Citrulline

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Arginine Caffeine-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.

Bioperine17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation. This has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

Theoretically, black pepper might increase blood levels of atorvastatin.
Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold. This has not been reported in humans.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, black pepper might increase the effects and side effects of cyclosporine.
In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine. This has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.
In vitro research suggests that some constituents of black pepper inhibit CYP2D6. This has not been reported in humans.

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

Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.
In vitro research and pharmacokinetic simulation data suggest that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4. This has not been reported in humans.

Likelihood Possible Evidence D
Lithium

Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.
Black pepper is thought to have diuretic properties.

Likelihood Probable Evidence D
Nevirapine (Viramune)

Black pepper might increase blood levels of nevirapine.
Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study.

Likelihood Probable Evidence D
P-Glycoprotein Substrates

Theoretically, black pepper might increase levels of P-glycoprotein substrates.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black pepper might increase the sedative effects of pentobarbital.
Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

Black pepper might increase blood levels of phenytoin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin. Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin. Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper.

Likelihood Possible Evidence B
Propranolol (Inderal)

Black pepper might increase blood levels of propranolol.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol.

Likelihood Possible Evidence B
Rifampin (Rifadin)

Black pepper might increase blood levels of rifampin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin.

Likelihood Possible Evidence B
Theophylline

Black pepper might increase blood levels of theophylline.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline.

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

Theoretically, black pepper might increase the effects and side effects of amoxicillin.
Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin. This has not been reported in humans.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.
One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects. In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner.

Likelihood Possible Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, black pepper might decrease levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that black pepper induces CYP1A2. This has not been reported in humans.

Likelihood Possible Evidence D
Bioperine full monograph & interactions

Vitamin D38 drug types · 715 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases 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 vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D
Vitamin D3 full monograph & interactions

L-Arginine9 drug types · 403 drugs

Ace Inhibitors (Aceis)

Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects. Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Angiotensin Receptor Blockers (Arbs)

Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
L-arginine increases nitric oxide, which causes vasodilation. Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation. Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
Preliminary research suggests that L-arginine infusions reduce platelet aggregation in humans. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
Preliminary clinical research shows that L-arginine decreases blood glucose levels in patients with type 2 diabetes.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
L-arginine increases nitric oxide, which causes vasodilation. Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension. Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects.

Likelihood Probable Evidence D
Isoproterenol (Isuprel)

Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
Potassium-sparing diuretics can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation. Theoretically, concurrent use might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
Testosterone

Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.

Likelihood Possible Evidence D
L-Arginine full monograph & interactions

Pine Bark Extract3 drug types · 327 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, maritime pine bark extract might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.
Clinical research suggests that maritime pine bark extract inhibits platelet aggregation. However, the clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, maritime pine bark extract might increase the risk of hypoglycemia when used with antidiabetes drugs.
One clinical study shows that maritime pine bark extract decreases blood sugar in patients with diabetes being treated with antidiabetes agents. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence B
Immunosuppressants

Theoretically, maritime pine bark extract might decrease the effectiveness of immunosuppressant therapy.
In vitro and animal research suggests that maritime pine bark extract has immunostimulant activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Pine Bark Extract full monograph & interactions

L-Citrulline2 drug types · 178 drugs

Antihypertensive Drugs

Theoretically, concomitant use of L-citrulline with antihypertensive drugs might have additive effects and increase the chance of hypotension.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. However, a meta-analysis of 5 small clinical studies suggests that taking L-citrulline 3-6 grams daily for 1-8 weeks does not lower blood pressure when compared with control.

Likelihood Possible Evidence B
Phosphodiesterase-5 Inhibitors

Theoretically, concurrent use of phosphodiesterase-5 (PDE-5) inhibitors and L-citrulline might result in additive vasodilation.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. Theoretically, taking L-arginine with PDE-5 inhibitors might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
L-Citrulline full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Arginine Caffeine-Free, from the product label.

SNAP

See all SNAP products
Name
SNAP Supplements
Street Address
11012 NE 39th St., Suite C5
City
Vancouver
State
WA
ZipCode
98682
Phone Number
1-888-491-5043
Web Address
snapsupplements.com
Pharmacist Counseling Corner

L-Arginine Caffeine-Free by SNAP: Common Questions

Does L-Arginine Caffeine-Free by SNAP interact with any medications?
Yes. Based on its ingredients, L-Arginine Caffeine-Free has a known interaction with 1,249 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Arginine Caffeine-Free contains 9 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 L-arginine safe to take if I'm pregnant or breastfeeding?
L-arginine is rated possibly safe in pregnancy. L-citrulline and pine bark extract have insufficient data—the facts advise against them during pregnancy and breastfeeding. Vitamin D3 is likely safe in pregnancy at recommended doses and likely safe while breastfeeding. Talk with your doctor or pharmacist about which ingredients are right for your situation.
Will this help me with athletic performance?
L-citrulline has possibly effective evidence for athletic performance. The other ingredients in this product don't have established effectiveness ratings for athletic performance in the data we hold.
What are the most common side effects I might experience?
From L-arginine: abdominal pain, bloating, nausea, diarrhea, headache, insomnia, and flushing. From L-citrulline: gastrointestinal discomfort and heartburn. From Bioperine: burning aftertaste and indigestion. From pine bark extract: dizziness and vertigo. These tend to be mild and occur in a small number of users.
Can I take this if I have asthma?
L-arginine when inhaled can cause airway inflammation, but two studies of oral L-arginine in people with asthma found no adverse airway effects. Pine bark extract is possibly effective for asthma. Talk with your doctor before starting, since you take it by mouth in capsule form.
Why is the product caffeine-free—does L-arginine normally have caffeine?
L-arginine itself has no caffeine. The product label specifies caffeine-free to make clear this won't give you caffeine-related side effects like jitteriness or sleep disruption.
Is this safe to take long-term?
L-arginine safety for self-treatment long-term is not well established. L-citrulline's long-term safety is not fully studied. Vitamin D3 is safe long-term at recommended doses. Pine bark extract's long-term safety isn't fully established. Talk with your doctor if you're planning to use this for more than a few weeks.

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

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L-Arginine Caffeine-Free label
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The Full Monographs Behind L-Arginine Caffeine-Free’s Ingredients

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

Herb & supplement monograph

Vitamin D

Interacts with 715 drugs

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...

Read the full Vitamin D monograph → Herb & supplement monograph

L-arginine

Interacts with 403 drugs

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for blood pressure, erectile dysfunction, and...

Read the full L-arginine monograph → Herb & supplement monograph

L-citrulline

Interacts with 178 drugs

L-citrulline is an amino acid that the body turns into L-arginine to help make nitric oxide, which relaxes blood vessels and may improve blood flow. It is popular for exercise performance an...

Read the full L-citrulline monograph → Herb & supplement monograph

Black Pepper

Interacts with 1,019 drugs

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to help the body absorb other ingredients (li...

Read the full Black Pepper monograph → Herb & supplement monograph

Maritime Pine

Interacts with 327 drugs

Maritime pine bark extract (often sold as Pycnogenol) is a plant-based antioxidant most studied for circulation, vein, and skin health. Some research is promising, but many studies are small...

Read the full Maritime Pine monograph →
Sources

Sources & How We Checked

L-Arginine Caffeine-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 143 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.

L-arginine 66 references
  1. Sapienza MA, Kharitonov SA, Horvath I, et al. Effect of inhaled L-arginine on exhaled nitric oxide in normal and asthmatic subjects. Thorax 1998;53:172-5.
  2. Clarkson P, Adams MR, Powe AJ, et al. Oral L-arginine improves endothelium-dependent dilation in hypercholesterolemic young adults. J Clin Invest 1996;97:1989-94. PubMed
  3. Tenenbaum A, Fisman EZ, Motro M. L-arginine: Rediscovery in progress. Cardiology 1998;90:153-9.
  4. Brittenden J, Park KGM, Heys SD, et al. L-Arginine stimulates host defenses in patients with breast cancer. Surgery 1994;115:205-12.
  5. Korting GE, Smith SD, Wheeler MA, et al. A randomized double-blind trial of oral L-arginine for treatment of interstitial cystitis. J Urol 1999;161:558-65. DOI
  6. Rector TS, Bank AJ, Mullen KA, et al. Randomized, double-blind, placebo-controlled study of supplemental oral L-arginine in patients with heart failure. Circulation 1996;93:2135-41.
  7. Siani A, Pagano E, Iacone R, et al. Blood pressure and metabolic changes during dietary L-arginine supplementation in humans. Am J Hypertens 2000;13:547-51. PubMed
  8. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  9. Wallace AW, Tom WL. Interaction of L-arginine and phosphodiesterase inhibitors in vasodilation of the porcine internal mammary artery. Anesth Analg 2000;90:840-6. DOI
  10. Huynh NT, Tayek JA. Oral arginine reduces systemic blood pressure in type 2 diabetes: its potential role in nitric oxide generation. J Am Coll Nutr 2002;21:422-7.. PubMed
  11. Staff AC, Berge L, Haugen G, et al. Dietary supplementation with L-arginine or placebo in women with pre-eclampsia. Acta Obstet Gynecol Scand 2004;83:103-7.
  12. Resnick DJ, Softness B, Murphy AR, et al. Case report of an anaphylactoid reaction to arginine. Ann Allergy Asthma Immunol 2002;88:67-8. PubMed
  13. Anon. Arginine hydrochloride injection (marketed as R-Gene 10). FDA Drug Safety Newsletter 2009;2(2):16-18. Available at: www.fda.gov/Drugs/DrugSafety/DrugSafetyNewsletter/default.htm.
  14. Higashi Y, Oshima T, Sasaki S, et. al. Angiotensin-converting enzyme inhibition, but not calcium antagonism, improves a response of the renal vasculature to L-arginine in patients with essential hypertension. Hypertension. 1998 Jul;32(1):16-24.
  15. Facchinetti, F., Longo, M., Piccinini, F., Neri, I., and Volpe, A. L-arginine infusion reduces blood pressure in preeclamptic women through nitric oxide release. J Soc Gynecol.Investig. 1999;6(4):202-207. DOI
  16. de Gouw, H. W., Verbruggen, M. B., Twiss, I. M., and Sterk, P. J. Effect of oral L-arginine on airway hyperresponsiveness to histamine in asthma. Thorax 1999;54(11):1033-1035. PubMed
  17. Komers, R., Komersova, K., Kazdova, L., Ruzickova, J., and Pelikanova, T. Effect of ACE inhibition and angiotensin AT1 receptor blockade on renal and blood pressure response to L-arginine in humans. J Hypertens. 2000;18(1):51-59. PubMed
  18. Cartledge, J. J., Davies, A. M., and Eardley, I. A randomized double-blind placebo-controlled crossover trial of the efficacy of L-arginine in the treatment of interstitial cystitis. BJU.Int. 2000;85(4):421-426.
  19. Sozykin, A. V., Noeva, E. A., Balakhonova, T. V., Pogorelova, O. A., and Men'shikov, M. I. [Effect of L-arginine on platelet aggregation, endothelial function adn exercise tolerance in patients with stable angina pectoris]. Ter.Arkh. 2000;72(8):24-27.
  20. Nagaya, N., Uematsu, M., Oya, H., Sato, N., Sakamaki, F., Kyotani, S., Ueno, K., Nakanishi, N., Yamagishi, M., and Miyatake, K. Short-term oral administration of L-arginine improves hemodynamics and exercise capacity in patients with precapillary pulmona
  21. Stokes, G. S., Barin, E. S., Gilfillan, K. L., and Kaesemeyer, W. H. Interactions of L-arginine, isosorbide mononitrate, and angiotensin II inhibitors on arterial pulse wave. Am J Hypertens. 2003;16(9 Pt 1):719-724.
  22. Park, K. G., Heys, S. D., Blessing, K., Kelly, P., McNurlan, M. A., Eremin, O., and Garlick, P. J. Stimulation of human breast cancers by dietary L-arginine. Clin.Sci.(Lond) 1992;82(4):413-417.
  23. Palloshi, A., Fragasso, G., Piatti, P., Monti, L. D., Setola, E., Valsecchi, G., Galluccio, E., Chierchia, S. L., and Margonato, A. Effect of oral L-arginine on blood pressure and symptoms and endothelial function in patients with systemic hypertension,
  24. Schlaich, M. P., Ahlers, B. A., Parnell, M. M., and Kaye, D. M. beta-Adrenoceptor-mediated, nitric-oxide-dependent vasodilatation is abnormal in early hypertension: restoration by L-arginine. J Hypertens. 2004;22(10):1917-1925. PubMed
  25. Neri, I., Blasi, I., and Facchinetti, F. Effects of acute L-arginine infusion on non-stress test in hypertensive pregnant women. J Matern.Fetal Neonatal Med. 2004;16(1):23-26. PubMed
  26. Rytlewski, K., Olszanecki, R., Korbut, R., and Zdebski, Z. Effects of prolonged oral supplementation with l-arginine on blood pressure and nitric oxide synthesis in preeclampsia. Eur.J Clin.Invest 2005;35(1):32-37.
  27. Mansoor, J. K., Morrissey, B. M., Walby, W. F., Yoneda, K. Y., Juarez, M., Kajekar, R., Severinghaus, J. W., Eldridge, M. W., and Schelegle, E. S. L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m. High Alt.M
  28. Neri, I., Jasonni, V. M., Gori, G. F., Blasi, I., and Facchinetti, F. Effect of L-arginine on blood pressure in pregnancy-induced hypertension: a randomized placebo-controlled trial. J Matern.Fetal Neonatal Med. 2006;19(5):277-281.
  29. Lucotti, P., Setola, E., Monti, L. D., Galluccio, E., Costa, S., Sandoli, E. P., Fermo, I., Rabaiotti, G., Gatti, R., and Piatti, P. Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in
  30. Savoye, G., Jemaa, Y., Mosni, G., Savoye-Collet, C., Morcamp, P., Dechelotte, P., Bouin, M., Denis, P., and Ducrotte, P. Effects of intragastric L-arginine administration on proximal stomach tone under basal conditions and after an intragastric diet. Dig PubMed
  31. Facchinetti, F., Saade, G. R., Neri, I., Pizzi, C., Longo, M., and Volpe, A. L-arginine supplementation in patients with gestational hypertension: a pilot study. Hypertens.Pregnancy. 2007;26(1):121-130. PubMed
  32. Jovanovic, A., Gerrard, J., and Taylor, R. The second-meal phenomenon in type 2 diabetes. Diabetes Care 2009;32(7):1199-1201. PubMed
  33. Fontanive P, Saponati G, Iurato A, et al. Effects of L-arginine on the Minnesota Living with Heart Failure Questionnaire quality-of-life score in patients with chronic systolic heart failure. Med.Sci.Monit. 2009;15:CR606-11.
  34. Doutreleau, S., Rouyer, O., Di, Marco P., Lonsdorfer, E., Richard, R., Piquard, F., and Geny, B. L-arginine supplementation improves exercise capacity after a heart transplant. Am J Clin.Nutr. 2010;91(5):1261-1267. PubMed
  35. Ast, J., Jablecka, A., Bogdanski, P., Smolarek, I., Krauss, H., and Chmara, E. Evaluation of the antihypertensive effect of L-arginine supplementation in patients with mild hypertension assessed with ambulatory blood pressure monitoring. Med.Sci.Monit. 2
  36. Saleh, A. I., Abdel Maksoud, S. M., El-Maraghy, S. A., and Gad, M. Z. Protective effect of L-arginine in experimentally induced myocardial ischemia: comparison with aspirin. J Cardiovasc.Pharmacol.Ther 2011;16(1):53-62. PubMed
  37. Dong, J. Y., Qin, L. Q., Zhang, Z., Zhao, Y., Wang, J., Arigoni, F., and Zhang, W. Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials. Am.Heart J 2011;162(6):959-965. PubMed
  38. Hertz, P. and Richardson, J. A. Arginine-induced hyperkalemia in renal failure patients. Arch.Intern.Med. 1972;130(5):778-780. DOI
  39. Bushinsky, D. A. and Gennari, F. J. Life-threatening hyperkalemia induced by arginine. Ann.Intern.Med. 1978;89(5 Pt 1):632-634. PubMed
  40. Adams, M. R., Forsyth, C. J., Jessup, W., Robinson, J., and Celermajer, D. S. Oral L-arginine inhibits platelet aggregation but does not enhance endothelium-dependent dilation in healthy young men. J Am Coll.Cardiol 1995;26(4):1054-1061. PubMed
  41. Dell'Omo, G., Catapano, G., Ebel, M., Gazzano, A., Ducci, M., Del, Chicca M., Clerico, A., and Pedrinelli, R. [Pressor, renal and endocrine effects of systemic infusion of L-arginine in hypertensive patients]. Ann.Ital Med.Int. 1995;10(2):107-112.
  42. Higashi, Y., Oshima, T., Ozono, R., Watanabe, M., Matsuura, H., and Kajiyama, G. Effects of L-arginine infusion on renal hemodynamics in patients with mild essential hypertension. Hypertension 1995;25(4 Pt 2):898-902.
  43. Bode-Boger, S. M., Boger, R. H., Creutzig, A., Tsikas, D., Gutzki, F. M., Alexander, K., and Frolich, J. C. L-arginine infusion decreases peripheral arterial resistance and inhibits platelet aggregation in healthy subjects. Clin.Sci.(Lond) 1994;87(3):303
  44. Marfella, R., Acampora, R., Verrazzo, G., Ziccardi, P., De, Rosa N., Giunta, R., and Giugliano, D. Metformin improves hemodynamic and rheological responses to L-arginine in NIDDM patients. Diabetes Care 1996;19(9):934-939. PubMed
  45. Giugliano, D., Marfella, R., Verrazzo, G., Acampora, R., Coppola, L., Cozzolino, D., and D'Onofrio, F. The vascular effects of L-Arginine in humans. The role of endogenous insulin. J Clin.Invest 2-1-1997;99(3):433-438. PubMed
  46. Khan, F., Litchfield, S. J., McLaren, M., Veale, D. J., Littleford, R. C., and Belch, J. J. Oral L-arginine supplementation and cutaneous vascular responses in patients with primary Raynaud's phenomenon. Arthritis Rheum. 1997;40(2):352-357.
  47. Wolf, A., Zalpour, C., Theilmeier, G., Wang, B. Y., Ma, A., Anderson, B., Tsao, P. S., and Cooke, J. P. Dietary L-arginine supplementation normalizes platelet aggregation in hypercholesterolemic humans. J Am Coll.Cardiol 3-1-1997;29(3):479-485. PubMed
  48. Schellong, S. M., Boger, R. H., Burchert, W., Bode-Boger, S. M., Galland, A., Frolich, J. C., Hundeshagen, H., and Alexander, K. Dose-related effect of intravenous L-arginine on muscular blood flow of the calf in patients with peripheral vascular disease
  49. Marietta, M., Facchinetti, F., Neri, I., Piccinini, F., Volpe, A., and Torelli, G. L-arginine infusion decreases platelet aggregation through an intraplatelet nitric oxide release. Thromb.Res 10-15-1997;88(2):229-235. PubMed
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  51. Vadillo-Ortega F, Perichart-Perera O, Espino S, et al. Effect of supplementation during pregnancy with L-arginine and antioxidant vitamins in medical food on pre-eclampsia in high risk population: randomised controlled trial. BMJ. 2011 May 19;342:d2901. PubMed
  52. Camarena Pulido EE, García Benavides L, Panduro Barón JG, et al. Efficacy of L-arginine for preventing preeclampsia in high-risk pregnancies: A double-blind, randomized, clinical trial. Hypertens Pregnancy. 2016;35(2):217-25. PubMed
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  54. Binet Q, Dufour I, Agneessens E, et al. The second case of a young man with L-arginine-induced acute pancreatitis. Clin J Gastroenterol. 2018;11(5):424-427. PubMed
  55. El Taieb M, Hegazy E, Ibrahim A. Daily oral l-arginine plus tadalafil in diabetic patients with erectile dysfunction: A double-blinded, randomized, controlled clinical trial. J Sex Med. 2019;16(9):1390-1397.
  56. Gallo L, Pecoraro S, Sarnacchiaro P, Silvani M, Antonini G. The daily therapy with L-arginine 2,500 mg and tadalafil 5 mg in combination and in monotherapy for the treatment of erectile dysfunction: A prospective, randomized multicentre study. Sex Med. 20 PubMed
  57. de la Parra PR, González-Cruz MÁ, Ferreiro-Marin A, Casaubón-Garcín PR. L-arginine-induced esophagitis, report of six cases. Bol Med Hosp Infant Mex. 2020;77(1):38-41. PubMed
  58. El-Wakeel LM, Fouad FA, Saleem MD, Saber-Khalaf M. Efficacy and tolerability of sildenafil/l-arginine combination relative to sildenafil alone in patients with organic erectile dysfunction. Andrology. 2020;8(1):143-147.
  59. Abu El-Hamd M, Hegazy EM. Comparison of the clinical efficacy of daily use of L-arginine, tadalafil and combined L-arginine with tadalafil in the treatment of elderly patients with erectile dysfunction. Andrologia. 2020;52(7):e13640. PubMed
  60. Liao SY, Showalter MR, Linderholm AL, et al. l-Arginine supplementation in severe asthma. JCI Insight. 2020;5(13):e137777. PubMed
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  63. Goto E. Effects of prenatal oral L-arginine on birth outcomes: a meta-analysis. Sci Rep 2021;11(1):22748. PubMed
  64. Monari F, Menichini D, Pignatti L, Basile L, Facchinetti F, Neri I. Effect of L-arginine supplementation in pregnant women with chronic hypertension and previous placenta vascular disorders receiving Aspirin prophylaxis: a randomized control trial. Minerv PubMed
  65. Li H, Liu Q, Zou Z, et al. L-arginine supplementation to mitigate cardiovascular effects of walking outside in the context of traffic-related air pollution in participants with elevated blood pressure: A randomized, double-blind, placebo-controlled trial. PubMed
  66. Shiraseb F, Asbaghi O, Bagheri R, Wong A, Figueroa A, Mirzaei K. The Effect of L-arginine Supplementation On Blood Pressure in Adults: A Systematic Review and Dose-response Meta-analysis of Randomized Clinical Trials. Adv Nutr 2021. PubMed

See these in context on the L-arginine monograph →

L-citrulline 8 references
  1. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  2. Schwedhelm E, Maas R, Freese R, et al. Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. Br J Clin Pharmacol 2008;65:51-9. PubMed
  3. Romero MJ, Platt DH, Caldwell RB, Caldwell RW. Therapeutic use of citrulline in cardiovascular disease. Cardiovasc Drug Rev 2006;24:275-90. PubMed
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  8. Xu Z, Liu C, Liu S, Zhou Z. Comparison of efficacy and safety of daily oral L-arginine and PDE5Is alone or combination in treating erectile dysfunction: A systematic review and meta-analysis of randomised controlled trials. Andrologia. 2021:e14007. PubMed

See these in context on the L-citrulline monograph →

Vitamin D 26 references
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Black Pepper 29 references
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Maritime Pine 14 references
  1. Rice-Evans CA, Packer L, eds. Flavonoids in Health and Disease. Manhattan, NY: Marcel Dekker, Inc., 1998.
  2. Liu FJ, Zhang YX, Lau BH. Pycnogenol enhances immune and haemopoietic functions in senescence-accelerated mice. Cell Mol Life Sci 1998;54:1168-72. PubMed
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  4. Kohama T, Inoue M. Pycnogenol alleviates pain associated with pregnancy. Phytother Res 2006;20:232-4.
  5. Liu X, Zhou HJ, Rohdewald P. French maritime pine bark extract pycnogenol dose-dependently lowers glucose in type 2 diabetic patients (letter). Diabetes Care 2004;27:839. PubMed
  6. Liu X, Wei J, Tan F, et al. Antidiabetic effect of Pycnogenol French maritime pine bark extract in patients with diabetes type II. Life Sci 2004;75:2505-13. 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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