Traditionally used for
- Teeth & mouth
- Cough & breathing
- Digestion
- Bowel health
☯ TCM Properties
Warms the Interior and Dispels Cold; Descends Qi; Dissolves Phlegm; Alleviates Pain; Strengthens the Spleen and Opens the Appetite
Traditional Chinese Uses
Hu Jiao (pepper, black and white pepper) is a warm, pungent herb used in Chinese medicine to warm the Stomach and Spleen, dispel cold from the interior, and relieve cold-type digestive symptoms including nausea, vomiting, abdominal pain, and diarrhea. White pepper — the ripe, dehusked form — is considered slightly more potent than black pepper medicinally. Its warming, penetrating nature addresses cold that has entered the digestive system, and it is also used topically for toothache from cold-type dental pain.
Western Herbalism Properties
Traditional Uses
Cherokee used Piper nigrum as an astringent dermatological aid and as a stimulant; both Cherokee and Haisla/Hanaksiala peoples employed it for seasoning food (Hamel and Chiltoskey, 1975, Cherokee Plants and Their Uses; Compton, 1993, Upper North Wakashan and Southern Tsimshian Ethnobotany).
Relationships
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Botanical Description
Piper nigrum, black pepper, is a perennial woody climbing vine in the Piperaceae, native to the Western Ghats of India and now widely cultivated across the wet tropics. The plant climbs by adventitious roots that emerge at the nodes, reaching 4 to 10 meters when supported on a tree or pole. The alternate leaves are simple, broadly ovate to elliptic, 10 to 18 cm long, with five to seven prominent palmate veins, a leathery dark green upper surface and a paler glaucous underside. The flowers are tiny, sessile and apetalous, densely arranged on slender, pendulous, axillary spikes 5 to 15 cm long. Each spike matures into a chain of small, single-seeded drupes 4 to 6 mm in diameter, green at first, ripening through red to almost black. The familiar black peppercorn is the entire dried fruit harvested while still green and ripening; white pepper is the same fruit ripened, soaked and rubbed free of the dark pericarp. The fruit contains the alkaloid piperine and a complex pungent essential oil.
Active Constituents
Piperine
Piperidine alkaloid (alkamide)Concentration: Roughly 2-9% of the dried unripe fruit (peppercorn), the single dominant alkaloid of the drug
Piperine is the pungent principle of the peppercorn and acts as an agonist at the human vanilloid receptor TRPV1, which accounts for the burning quality and for the reflex gastric and salivary secretion behind the traditional "opens the appetite" indication. Pharmacologically it is more important as a bioenhancer: it inhibits intestinal and hepatic CYP3A4 and the efflux transporter P-glycoprotein, so co-ingested drugs and phytochemicals reach higher plasma concentrations.
Piperettine, piperanine and piperyline
Minor piperidine alkamidesConcentration: Minor, together well under 1% of the dried fruit
Structural congeners of piperine that contribute to the total alkamide load and to pungency. They are far less studied than piperine and no separate clinical pharmacology is established for them.
beta-Caryophyllene
Bicyclic sesquiterpene hydrocarbonConcentration: The principal sesquiterpene of black pepper essential oil, commonly around 10-30% of the oil depending on cultivar
The dominant sesquiterpene of the volatile fraction and a selective cannabinoid CB2 receptor agonist, which is the usual explanation offered for the anti-inflammatory activity of pepper oil. It contributes the woody-spicy note of the oil rather than the pungency.
Sabinene, beta-pinene, alpha-pinene, limonene and delta-3-carene
Monoterpene hydrocarbonsConcentration: Collectively the largest fraction of the essential oil; the oil itself is roughly 1-4% of the dried fruit
These monoterpenes give black pepper its fresh aromatic top note and vary markedly between cultivars and between the aerial parts and the fruit. They are carminative and mildly antimicrobial in vitro but are not responsible for the drug's pungency or its drug-interaction profile.
Black pepper essential oil
Volatile terpenoid mixtureConcentration: About 1-4% of the dried fruit, obtained by hydrodistillation
The volatile fraction as a whole is what carries the aroma and the carminative action; it is chemically distinct from the non-volatile alkamide fraction that carries the pungency and the pharmacokinetic interactions. A monograph or product describing "black pepper oil" is therefore not describing piperine.
⚠ Drug Interactions
Phenytoin
Piperine inhibits the CYP enzymes and intestinal efflux that clear phenytoin. Bano and colleagues showed in healthy volunteers in 1987 that a single 20 mg dose of piperine raised phenytoin plasma concentrations, and Pattanaik and colleagues then confirmed the effect at steady state in epilepsy patients already stabilised on phenytoin (Phytotherapy Research, 2006), where added piperine significantly increased Cmax and AUC. Phenytoin has saturable kinetics, so a modest inhibition of clearance can produce a disproportionate rise in level.
Clinical note: Do not add Hu Jiao in therapeutic doses, piperine supplements or piperine-containing bioavailability enhancers to a patient stabilised on phenytoin without arranging serum level monitoring. Culinary quantities of pepper are a much smaller exposure than a standardised piperine supplement and have not been shown to matter; the concern is the concentrated extract.
Carbamazepine
Carbamazepine is a CYP3A4 substrate and piperine inhibits CYP3A4. Pattanaik and colleagues gave a single dose of piperine to epilepsy patients at steady state on carbamazepine and recorded a significant rise in exposure (Phytotherapy Research, 2009); Bedada and colleagues reproduced the effect in healthy volunteers after ten days of piperine 20 mg daily (Drug Research, 2016), reporting a substantial increase in AUC. This is human, not preclinical, evidence.
Clinical note: Treat concurrent piperine supplementation as a reason to check a carbamazepine level. Warn patients that "black pepper extract" and "BioPerine" on a supplement label are the same interacting substance.
CYP3A4 substrates with a narrow therapeutic index (ciclosporin, tacrolimus, and similar)
Bhardwaj and colleagues demonstrated directly in human tissue that piperine inhibits both P-glycoprotein and CYP3A4 (Journal of Pharmacology and Experimental Therapeutics, 2002). A 2023 systematic review and meta-analysis of human pharmacokinetic studies concluded that piperine measurably alters the disposition of CYP3A4, CYP2C9 and CYP2E1 substrates, and a 2024 PBPK modelling study predicted clinically relevant food-drug interactions between dietary piperine and CYP3A4 substrates. The class effect is therefore supported by human data even where the individual drug has not been tested.
Clinical note: For transplant, oncology and antiretroviral patients on narrow-index CYP3A4 substrates, avoid concentrated piperine products and record dietary pepper intake if levels are unexpectedly high or unstable.
P-glycoprotein substrates (fexofenadine, digoxin and similar)
Bedada and Boga gave piperine to healthy volunteers and measured a significant increase in the exposure of fexofenadine, a clean P-glycoprotein probe with negligible CYP metabolism (European Journal of Clinical Pharmacology, 2016), isolating transporter inhibition from enzyme inhibition. The in vitro basis is Bhardwaj 2002. Digoxin has not been tested directly with piperine in humans, so it is an inference from shared transporter handling rather than a measured interaction.
Clinical note: With digoxin, which combines P-glycoprotein handling with a narrow therapeutic index, avoid concentrated piperine and monitor if it has already been taken.
Propranolol and theophylline
Bano and colleagues gave piperine 20 mg daily for seven days to healthy volunteers and found significantly increased bioavailability and AUC for both propranolol and theophylline (European Journal of Clinical Pharmacology, 1991). Theophylline in particular has a narrow therapeutic index, so a bioavailability rise can cross into toxicity.
Clinical note: Ask about piperine or black pepper extract supplements when theophylline levels drift upward without a dose change.
Diclofenac and other NSAIDs
Bedada and colleagues showed in healthy volunteers that piperine pretreatment significantly increased diclofenac exposure (Xenobiotica, 2016), consistent with inhibition of CYP2C9 and CYP3A4. Pepper is itself a gastric irritant at therapeutic dose, so the pharmacokinetic and pharmacodynamic risks compound.
Clinical note: Avoid combining therapeutic-dose Hu Jiao or piperine supplements with chronic NSAID use, particularly in patients with reflux, gastritis or ulcer history.
Curcumin and other poorly absorbed phytochemical supplements
Shoba and colleagues showed in human volunteers that piperine 20 mg raised curcumin bioavailability roughly twenty-fold (Planta Medica, 1998), which is why piperine is deliberately added to most commercial turmeric products. The practical consequence is that a piperine-containing turmeric product is a much larger curcumin exposure than the label dose suggests, and curcumin's own antiplatelet and CYP effects scale with it.
Clinical note: When reviewing a patient's turmeric supplement, check whether it contains piperine or "BioPerine" before judging the dose, and count the piperine itself as an active drug-interacting ingredient.
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction, or powder/pills | 0.6–1.5 g | Daily | — | — | 中国药典 2020 【用法与用量】0.6～1.5g，研粉吞服。外用适量。 【性味与归经】辛，热。归胃、大肠经。 — Chinese Pharmacopoeia 2020, quoted verbatim; route and cautions preserved. Replaces a cleared category-filler value. |
Evidence Tier
Strong evidence · 12 studiesRecorded studies by study design, strongest design at the top. This is a study-design tier only, not a GRADE rating: it does not weigh risk of bias, consistency or precision.
Systematic review / meta-analysis
1
0 verified · 1 unverified
Randomized controlled trial
5
0 verified · 5 unverified
Show 5 studies
- Effect of piperine on the steady-state pharmacokinetics of phenytoin in patients with epilepsy
- The influence of piperine on the pharmacokinetics of fexofenadine, a P-glycoprotein substrate, in healthy volunteers
- Study on influence of piperine treatment on the pharmacokinetics of diclofenac in healthy volunteers
- Effect of piperine on bioavailability and pharmacokinetics of propranolol and theophylline in healthy volunteers
- The Effect of Piperine on Pharmacokinetics of Phenytoin in Healthy Volunteers
Other clinical trial
3
3 verified · 0 unverified
Show 3 studies
Observational / case report
0
In vitro / animal
3
0 verified · 3 unverified
Show 3 studies
Other / unclassified
0
Verified: design read from PubMed for a DOI that resolves to the cited paper Unverified: taken from the study's recorded description
Clinical Studies
Cytochrome P450-mediated alterations in clinical pharmacokinetic parameters of conventional drugs coadministered with piperine: a systematic review and meta-analysis
Systematic review with meta-analysis of human pharmacokinetic studies in which piperine was coadministered with, or given before, conventional drugs. The pooled analysis supports piperine acting as an inhibitor of CYP3A4, CYP2C9 and CYP2E1 substrate metabolism in healthy volunteers, and the authors flag the risk this poses for narrow-therapeutic-index drugs. This is the highest-tier evidence available for the black pepper interaction question.
Piperine, a Major Constituent of Black Pepper, Inhibits Human P-glycoprotein and CYP3A4
The mechanistic foundation for every black pepper interaction warning. Using human P-glycoprotein-overexpressing cells and human CYP3A4 preparations, the authors showed that piperine inhibits both the efflux transporter and the enzyme at concentrations plausibly reached after dietary or supplemental intake. In vitro only, but in human systems rather than rodent.
Effect of piperine on the steady-state pharmacokinetics of phenytoin in patients with epilepsy
Controlled human study in epilepsy patients already at steady state on phenytoin. Adding piperine significantly increased phenytoin exposure, converting a laboratory finding about CYP inhibition into a demonstrated clinical risk in the exact population most likely to be harmed by it.
Pharmacokinetic interaction of single dose of piperine with steady-state carbamazepine in epilepsy patients
Companion study to the same group's phenytoin work. A single piperine dose given to epilepsy patients on stable carbamazepine significantly raised carbamazepine exposure, showing that the interaction does not require chronic piperine dosing to appear.
Effect of Piperine on the Metabolism and Pharmacokinetics of Carbamazepine in Healthy Volunteers
Healthy-volunteer crossover study in which ten days of piperine 20 mg daily substantially increased carbamazepine AUC and Cmax and reduced its clearance, reproducing the patient finding in a controlled healthy population and attributing it to CYP3A4 inhibition.
The influence of piperine on the pharmacokinetics of fexofenadine, a P-glycoprotein substrate, in healthy volunteers
Healthy-volunteer study using fexofenadine, which is cleared almost entirely by transporters rather than by CYP metabolism, as a clean probe. Piperine significantly increased fexofenadine exposure, isolating P-glycoprotein inhibition as a mechanism in humans independent of enzyme inhibition.
Study on influence of piperine treatment on the pharmacokinetics of diclofenac in healthy volunteers
Healthy-volunteer crossover study showing that piperine pretreatment significantly increased diclofenac AUC and Cmax and decreased its oral clearance, consistent with inhibition of the CYP2C9 and CYP3A4 pathways that handle the NSAID.
Effect of piperine on bioavailability and pharmacokinetics of propranolol and theophylline in healthy volunteers
Early human crossover study in which piperine 20 mg daily for seven days significantly raised the bioavailability and AUC of both propranolol and theophylline, one of the first demonstrations that black pepper's alkaloid alters conventional drug disposition in people rather than only in rodents.
The Effect of Piperine on Pharmacokinetics of Phenytoin in Healthy Volunteers
The original human demonstration that a single 20 mg dose of piperine raises phenytoin plasma concentrations and bioavailability in healthy volunteers, later confirmed at steady state in epilepsy patients.
Influence of Piperine on the Pharmacokinetics of Curcumin in Animals and Human Volunteers
The study that made piperine a standard supplement excipient. In human volunteers, 20 mg of piperine with 2 g of curcumin increased curcumin bioavailability roughly twentyfold with no reported adverse effects at that single dose. Practitioners should read it as evidence that piperine is a potent, deliberately exploited absorption modifier, not an inert spice.
Predicting Food-Drug Interactions between Piperine and CYP3A4 Substrate Drugs Using PBPK Modeling
Physiologically based pharmacokinetic modelling of dietary and supplemental piperine against CYP3A4 substrate drugs. The simulations predict interactions of a magnitude that matters clinically for narrow-therapeutic-window drugs, and the authors argue that piperine exposure should be considered when such drugs are dosed. Modelling and simulation rather than a new human trial.
Effects of piperine, the pungent component of black pepper, at the human vanilloid receptor (TRPV1)
Electrophysiological characterisation of piperine at cloned human TRPV1, showing it to be a potent agonist with a distinct profile from capsaicin. This is the molecular basis of the drug's pungency and of the traditional description of Hu Jiao as acrid and hot.
Historical Texts
Xin Xiu Ben Cao (Newly Revised Materia Medica, also called Tang Ben Cao), compiled under Su Jing
Tang dynasty, 659 CE (Chinese tradition)Ben Cao Gang Mu, Li Shizhen
Ming dynasty, completed 1578, first printed 1596 (Chinese tradition)Charaka Samhita (maricha, a component of the trikatu formula with Piper longum and Zingiber officinale)
Ayurvedic classical period, compiled by roughly the 2nd century CE (Ayurvedic tradition)De Materia Medica, Pedanius Dioscorides
Roman period, circa 65 CE (Greco-Roman and later Western tradition)References
- Srinivasan K. Black Pepper and its Pungent Principle-Piperine: A Review of Diverse Physiological Effects . Critical Reviews in Food Science and Nutrition (2007) [DOI]
- Srinivasan K. Black Pepper (Piper nigrum) and Its Bioactive Compound, Piperine . Molecular Targets and Therapeutic Uses of Spices (2009) [DOI]
- Menon AN, Padmakumari KP, Jayalekshmy AJ. Essential Oil Composition of Four Major Cultivars of Black Pepper (Piper nigrum L.) . Journal of Essential Oil Research (2002) [DOI]
- Milenkovic A, Stanojevic J, Cvetkovic D, Stanojevic L. Chemical composition and antioxidant activity of black pepper (Piper nigrum L.) fructus essential oil hydrodistillation fractions . Journal of Essential Oil Bearing Plants (2024) [DOI]
- Pino JA, Aguero J, Fuentes V. Chemical Composition of the Aerial Parts of Piper nigrum L. from Cuba . Journal of Essential Oil Research (2003) [DOI]
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.
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