Materia Medica

Piper nigrum (Black Pepper) plant, realistic botanical photo
Black Pepper (Piper nigrum) — Peppercorn, Kali Mirch
A whole-plant guide to black pepper covering the climbing vine, peppercorn processing, culinary history, piperine research, traditional use, interactions, and safety. Read more...
Parsley leaf (Petroselinum crispum)
Parsley (Petroselinum crispum) — Garden Parsley, Curly Parsley
A whole-plant guide to parsley (Petroselinum crispum), covering the living plant, leaves, root, flowers and seed, cut-and-sifted and powdered forms, culinary preparations, traditional herbal context, research, safety and folklore. Read more...
Passionflower (Passiflora incarnata) — Maypop, Apricot Vine
A guide to Passiflora incarnata covering passionflower's traditional calming use, anxiety and sleep research, sedation interactions, pregnancy caution and folklore. Read more...
Peppermint (Mentha × piperita) — Brandy Mint, Balm Mint
A guide to Mentha × piperita covering peppermint tea, IBS research on enteric-coated oil, reflux cautions, infant menthol safety and folklore. Read more...
Plantain (Plantago major & Plantago lanceolata) — Common Plantain, Ribwort, White Man's Foot
A guide to Plantago major and P. lanceolata covering plantain leaf identification, traditional poultice and tea use, psyllium differences and safety. Read more...
Poison Hemlock (Conium maculatum) — Deadly Hemlock, Spotted Hemlock
A poison-first guide to Conium maculatum covering lethal alkaloids, identification, dangerous edible look-alikes, poisoning symptoms, safe handling and removal, Washington legal restrictions, and history. Read more...
Partridgeberry (Mitchella repens) — Twinberry, Squaw Vine, Checkerberry
A research-grounded guide to partridgeberry or twinberry (Mitchella repens), covering woodland identification, Indigenous and folk women’s-use traditions, floral chemistry, major modern research gaps and pregnancy safety concerns. Read more...
Patchouli (Pogostemon cablin) — Guang Huo Xiang, Patchouly
A research-grounded guide to patchouli (Pogostemon cablin), also known as Guang Huo Xiang, covering perfumery, traditional Chinese herbal use, patchouli alcohol and other constituents, evidence limits, flavoring status and fragrance-allergy safety. Read more...
Pau d'Arco (Handroanthus impetiginosus) — Taheebo, Lapacho
A research-grounded guide to pau d’arco, taheebo or lapacho (Handroanthus impetiginosus; formerly Tabebuia impetiginosa), covering traditional inner-bark use, lapachol and beta-lapachone research, cancer-claim evidence limits, bleeding concerns and pregnancy safety. Read more...
Pennyroyal (Mentha pulegium) — European Pennyroyal, Pudding Grass
A safety-first guide to pennyroyal (Mentha pulegium), covering traditional use, pulegone and menthofuran toxicology, severe essential-oil poisoning, pregnancy danger, liver injury and emergency safety considerations. Read more...
Lesser Periwinkle (Vinca minor) — Common Periwinkle, Running Myrtle
A safety-focused guide to lesser or common periwinkle (Vinca minor), covering vincamine and other indole alkaloids, traditional use, older clinical evidence, the distinction from synthetic vinpocetine and Madagascar periwinkle, and internal-use cautions. Read more...
Peruvian Bark (Cinchona spp.) — Cinchona, Jesuit's Bark, Quinine Bark
A safety-focused guide to Peruvian bark and Cinchona species, covering Indigenous and colonial history, quinine’s antimalarial legacy, cinchonism, blood and kidney reactions, cardiac risks, drug interactions and why bark is not equivalent to prescription quinine. Read more...