Materia Medica

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...
Pine (Pinus spp.) — Scots Pine, White Pine, Pine Needles
A research-grounded guide to true pine (Pinus spp.), focusing on Scots pine and Eastern white pine, traditional uses, chemistry, food context, essential-oil distinctions, yew look-alike danger and safety. Read more...
Pineapple (Ananas comosus) — Bromelain, Ananas
A research-grounded guide to pineapple (Ananas comosus) and bromelain, separating ordinary food use from concentrated enzyme supplements while covering postoperative evidence, allergy and latex/pollen cross-reactivity, GI effects, bleeding-interaction cautions and pregnancy evidence limits. Read more...
Pipsissewa (Chimaphila umbellata) — Prince's Pine, Wintergreen
A research-grounded guide to pipsissewa / prince’s pine (Chimaphila umbellata), covering traditional urinary and diuretic use, chimaphilin and arbutin-related chemistry, modern evidence limits, skin sensitivity, pregnancy and kidney cautions, and responsible sourcing. Read more...
Pleurisy Root (Asclepias tuberosa) — Butterfly Weed, Orange Milkweed
A safety-first guide to pleurisy root / butterfly weed (Asclepias tuberosa), covering historic respiratory use, variable milkweed cardenolide chemistry, evidence limits, poisoning and heart-medication cautions, pregnancy safety, identification, and responsible sourcing. Read more...
Poke Root (Phytolacca americana) — Pokeweed, Pokeberry, Inkberry
A safety-first guide to poke root / American pokeweed (Phytolacca americana), covering traditional use, identification, toxic saponins and ribosome-inactivating proteins, poisoning symptoms, pregnancy concerns, evidence limits, and why the root should not be used as a DIY medicinal preparation. Read more...
Pomegranate (Punica granatum) — Granate, Punic Apple
A research-grounded guide to pomegranate (Punica granatum), separating fruit and juice from concentrated extracts and root/stem bark while covering polyphenols, cardiovascular and metabolic research, medication interactions, pregnancy cautions and safety. Read more...
Prickly Ash (Zanthoxylum americanum) — Northern Prickly Ash, Toothache Tree
A research-grounded guide to northern prickly ash (Zanthoxylum americanum), covering toothache-tree history, bark and berry use, pungent alkylamide chemistry, evidence limits, pregnancy cautions, species confusion and responsible sourcing. Read more...
Quince (Cydonia oblonga) — Quince Apple, Cydonia
Quince (Cydonia oblonga) is an aromatic Rosaceae fruit with a long culinary and traditional-medicine history. This guide separates ordinary quince fruit from leaves, concentrated extracts and seed preparations; reviews the limited human research on reflux and nausea; and explains why quince seeds and cyanogenic compounds deserve separate safety attention. Read more...
Red Root (Ceanothus americanus) — New Jersey Tea, Mountain Sweet
Red root or New Jersey tea (Ceanothus americanus) is a native North American shrub with a Revolutionary-era leaf-tea history and a separate medicinal root tradition. This full guide covers Indigenous and American herbal history, leaf-versus-root preparation, ceanothane triterpenes, lymphatic and spleen traditions, sustainability, growing, harvesting and safety. Read more...
Rose (Rosa × damascena) — Damask Rose, Rose Petals
Rose flowers and petals—especially Damask rose (Rosa × damascena)—have a long history in tea, rose water, syrups, preserves, skin care and traditional herbalism. This full guide covers practical preparations, petal chemistry, human research, harvesting, drying, growing, folklore, safety and the important differences among petals, rose hips, rose water and essential oil. Read more...