Benefits
Higher curcumin blood levels when taken together with curcumin
In healthy volunteers, adding 20 mg piperine to a 2 g dose of curcumin raised curcumin bioavailability by about 2,000% compared with curcumin alone, likely by slowing glucuronidation in the gut wall and liver. This measured blood levels after a single dose, not a health outcome. It is the reason many turmeric products include black pepper extract.
Lower fasting glucose and triglycerides versus placebo in one 12 week trial
In a double blind trial, 68 adults with fatty liver and without diabetes took 5 mg piperine or placebo daily for 12 weeks. At the end, fasting glucose was 93.5 vs 102.5 mg/dL and triglycerides 157 vs 214 mg/dL, but HOMA insulin resistance and HbA1c did not differ between groups. Cholesterol differed at baseline, and the authors call the result a very preliminary trend.
Effect on absorption of other nutrients depends on the compound
Reviews describe piperine as a bioenhancer for many drugs and nutrients, largely from laboratory and animal work. In people the picture varies: in two randomized studies, adding 5 to 25 mg piperine to resveratrol did not significantly change resveratrol blood levels. More of a nutrient reaching the blood is also not the same as a benefit you can feel.
Generic and branded piperine extracts
Generic black pepper extracts standardized to 95% or more piperine contain the same active compound as branded BioPerine®. No study cited on this page compares a branded extract against a generic one, so any claim that one outperforms the other is not supported here.
Drug interaction caution: higher blood levels of some medicines
In small human studies, piperine taken once or daily for up to 10 days raised blood levels of carbamazepine, phenytoin and nevirapine. Laboratory work shows it blocks CYP3A4 and P-glycoprotein, which clear many prescription drugs. A German risk assessment review warns this may cause unintended adverse drug effects, so ask a pharmacist or doctor first if you take any medicine.
Mechanism of action
CYP3A4 and P-glycoprotein inhibition
In laboratory tests with human intestinal cells and liver microsomes, piperine blocked the P-glycoprotein pump that pushes compounds back out of gut cells and slowed the CYP3A4 enzyme. Both work in the gut wall and liver, so blocking them can let more of a co-administered nutrient or drug reach the blood. A human carbamazepine study points the same way.
UDP-glucuronyl transferase inhibition
Piperine inhibits UDP-glucuronyl transferase enzymes in the liver and intestine, which attach a tag that helps the body remove many nutrients and drugs. Slowing that step is the proposed reason it raises curcumin levels. The same effect can apply to medicines, which is why the interaction caution matters.
Clinical trials
Pharmacokinetic study in rats and in healthy human volunteers comparing a single 2 g dose of curcumin alone with 2 g curcumin plus 20 mg piperine. It measured blood levels only, not any health outcome (Shoba et al. 1998, Planta Med)
Healthy adult volunteers (the same paper also reports rat experiments).
With curcumin alone, serum curcumin was undetectable or very low. Adding 20 mg piperine gave much higher levels from 15 minutes to 1 hour after dosing and raised curcumin bioavailability by about 2,000%. This was a single dose study of blood levels, so it shows better absorption, not a change in how anyone felt or functioned.
Randomized double blind placebo controlled trial in Iran in adults with grade 2 or 3 fatty liver on ultrasound and raised ALT; people with diabetes were excluded. Capsules were supplied by Kimia Faravar Boali Co.; the authors declare no competing interests. Baseline cholesterol and HDL differed between groups, and the authors describe a very preliminary trend (Nouri-Vaskeh et al. 2024, Sci Rep)
68 adults (34 per group), average age about 42.
After 12 weeks, fasting glucose was 93.5 vs 102.5 mg/dL (p = 0.011) and triglycerides 157 vs 214 mg/dL (p = 0.005) in the piperine group versus placebo. HOMA insulin resistance (p = 0.596) and HbA1c (p = 0.767) did not differ between groups. No side effects were reported.
Randomized double blind placebo controlled crossover study comparing placebo, 250 mg trans-resveratrol, and 250 mg trans-resveratrol plus 20 mg piperine on separate days. The main outcomes were frontal cortex blood flow and cognitive tasks; resveratrol plasma levels were checked in a separate group of 6 (Wightman et al. 2014, Br J Nutr)
23 adults, plus a separate group of 6 for blood level measurements.
Plasma resveratrol and its metabolites did not differ significantly between resveratrol alone and resveratrol plus piperine. The combination increased frontal cortex blood flow during the tasks compared with placebo and resveratrol alone, but cognitive performance, mood and blood pressure were not affected.
Randomized double blind three arm pilot trial of a single 2.5 g resveratrol dose with 0, 5 or 25 mg piperine, following earlier work in mice (Bailey et al. 2021, Eur J Cancer Prev)
24 healthy volunteers.
No significant relationship between piperine dose and resveratrol blood levels was found, so piperine did not reproduce the large boost seen in mice. Participants tolerated all three regimens with minimal to no toxicity and no differences between groups.
Randomized placebo controlled six way crossover study of a commercial curcuminoid plus piperine extract (4 g curcuminoids plus 24 mg piperine, given four times over 2 days) before midazolam, flurbiprofen or paracetamol. Two co-authors were affiliated with Sabinsa Corporation (Volak et al. 2013, Br J Clin Pharmacol)
8 healthy volunteers.
Compared with placebo, the extract produced no meaningful change in peak level, total exposure, clearance or half life of midazolam, flurbiprofen or paracetamol. The authors conclude short term use is unlikely to cause a clinically significant interaction through those pathways; it does not cover other drugs.
Open label two period sequential study: a single 200 mg carbamazepine dose before and after 10 days of 20 mg piperine daily (Bedada et al. 2017, Drug Res (Stuttg))
12 healthy volunteers.
After piperine, carbamazepine peak level rose by 68.7%, total exposure (AUC) by 47.9% and half life by 43.2%, while clearance fell by 38.9%. The authors attribute this to CYP3A4 inhibition and advise caution when piperine is combined with drugs cleared by CYP3A4.
Before and after study in people with uncontrolled epilepsy on steady state phenytoin (150 or 200 mg twice daily); phenytoin levels were measured on one day without and the next day with a single 20 mg piperine dose (Pattanaik et al. 2006, Phytother Res)
20 adults already taking phenytoin, in two dose groups of 10.
A single 20 mg piperine dose significantly raised phenytoin blood levels at most time points, with higher AUC(0-12h) (p < 0.01) and peak level (p < 0.001) than phenytoin alone.
Randomized crossover placebo controlled pilot study: 20 mg piperine or placebo daily for 6 days, then 200 mg nevirapine with piperine or placebo on day 7 (Kasibhatta et al. 2007, Drugs R D)
8 healthy men aged 20 to 40.
With piperine, nevirapine peak level rose by about 120% and total exposure (AUC) by about 167% compared with placebo. The authors call for larger studies.