Long pepper

Pharmacognosy & Toxicology

Constituents

• piperine ChEMBL3–5 per cent, the pungency
• piperlongumine ChEMBLan amide of research interest
• pipernonaline ChEMBL

Mechanism

Piperine activates TRPV1, the capsaicin receptor, which is the heat and the reflex rise in digestive secretion; it also inhibits the liver enzymes CYP3A4 and glucuronidation and raises blood levels of many drugs, the basis of the Ayurvedic practice of pairing peppers with other remedies. Piperlongumine is studied as an anticancer lead, though the Nature paper that launched it (Raj et al., 2011) was retracted in 2018.

Checked against ChEMBL

• piperine: Measured, as the entry says (“activates TRPV1”): Transient receptor potential cation channel subfamily V member 1 (human), EC50 3.2 µM, CHEMBL1158557.

Toxic dose

Safe as a spice; piperine at 20 mg raises curcumin absorption twentyfold (Shoba, 1998) and can do the same to drugs.

Standing

In the Ayurvedic pharmacopoeia (pippali); piperlongumine is in preclinical cancer work.

• Shoba, G., et al. (1998). “Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers.” Planta Medica 64. Verified against its record · doi:10.1055/s-2006-957450
• Raj, L., et al. (2011). “Selective killing of cancer cells by a small molecule targeting the stress response to ROS.” Nature 475; retracted 2018 (Nature 561). Verified against its record · doi:10.1038/nature10167

The abstract of each source, beneath its citation. For Club members. About the Club or sign in.

Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.