HerbMate

Herb comparison

Black Pepper (Piper nigrum) vs Evening Primrose (Oenothera biennis)

Both plants are listed as traditional remedies for 2 of the same conditions, which is why they are easy to confuse. Their descriptions and full safety notes are below, free.

Black Pepper (Piper nigrum) plant

Black Pepper (Piper nigrum)

Evening Primrose (Oenothera biennis) plant

Evening Primrose (Oenothera biennis)

About
Black pepper is a perennial woody climbing vine growing to about 16 feet, with large oval leaves, spikes of small white flowers, and clusters of small round fruits that ripen from green to red. Native to southwestern India and now cultivated in tropical areas worldwide, the fruit is harvested from plants that are at least three years old. Different processing methods yield green, black, red, and white peppercorns, each with distinct flavors and uses. Cultivated as both a spice and medicine since ancient times, pepper was such a prized commodity in world trade that Attila the Hun reportedly demanded 3,000 pounds of it as ransom during his siege of Rome in 408 CE.
Biennial herb growing to 8 in (20 cm). Has red blotches on stem, crinkled lance-shaped leaves, 4-petaled yellow flowers, and elongated seed capsules. The flowers, leaves, and stem bark of evening primrose have astringent and sedative properties. All three parts have been employed in the treatment of whooping cough. Evening primrose has also been taken for digestive problems and asthma, and used as a poultice to ease the discomfort of rheumatic disorders.
Safety & precautions
Large doses can cause gastrointestinal irritation in some individuals. Do not take the essential oil internally without professional supervision. Piperine significantly increased the AUC of nevirapine, theophylline, propranolol, phenytoin, and rifampicin in clinical and animal studies, suggesting caution when combining black pepper supplements with these medications. It may also inhibit cytochrome P450 enzymes (particularly CYP3A4, CYP2D6, and CYP2C), P-glycoprotein, and glucuronidation pathways, potentially affecting the metabolism of various drugs. High-dose piperine showed antithyroid effects in animals. Although pepper is generally safe as a culinary spice, concentrated piperine-containing supplements warrant careful use alongside medications.
Do not take evening primrose oil if suffering from epilepsy.

Safety text above is printed in full and is never abbreviated. For each plant’s complete precautions, drug and food interactions and preparation notes, open its own page - both are free.

Conditions that list both