Marigold (Calendula officinalis), or calendula, has a long history of use in treating wounds and soothing skin.
Marsh mallow (Althaea officinalis) has been used for over 2,000 years as both a food and a medicine.
Milk thistle (Silybum marianum) has been used for thousands of years for a variety of medicinal purposes, in particular liver problems.
Neem (Azadirachta indica), used in India to treat worms, malaria, rheumatism and skin infections among many other things. Its many uses have led to neem being called "the village dispensary" in India.
Noni (Morinda citrifolia) has a history of use as for joint pain and skin conditions.
Opium Poppy (Papaver somniferum) is the plant source of morphine, used for pain relief. Morphine made from the refined and modified sap is used for pain control in terminal patients. Dried sap was used as a traditional medicine until the 19th century.
Papaya (Carica papaya) is used for treating wounds.
Peppermint (Mentha x piperita) oil, from a cross between water mint and spearmint, has a history of medicinal use for a variety of conditions, including nausea, indigestion, and symptoms of the common cold.
Purple coneflower (Echinacea purpurea) and other species of Echinacea has been used for at least 400 years by Native Americans to treat infections and wounds, and as a general "cure-all". It is currently used for symptoms associated with cold and flu.
Red clover (Trifolium pratense) has been used historically to treat cancer and respiratory problems. More recently, it has been used for women's health issues.
Sage (Salvia officinalis), shown to improve cognitive function in patients with mild to moderate Alzheimer's disease.
St. John's wort (Hypericum perforatum), evaluated for use as an antidepressant, but with ambiguous results.
Saw palmetto (Serenoa repens) was used medicinally by the Seminole tribe.
Tea tree oil (Melaleuca alternifolia) has been used medicinally for centuries by Australian aboriginal people. Modern usage is primarily as an antibacterial or antifungal agent.
Thunder God Vine (Tripterygium wilfordii) is used in traditional Chinese medicine to treat inflammation or an overactive immune system.
Thyme (Thymus vulgaris) is used to treat bronchitis and cough. It serves as an antispasmotic and expectorant in this role. It has also been used in many other medicinal roles in Asian and Ayurvedic medicine, although it has not been shown to be effective in non-respiratory medicinal roles.
Tulasi (Ocimum tenuiflorum or Holy Basil) is used for a variety of purposes in Aryuvedic medicine.
Turmeric (Curcuma longa), a spice that lends its distinctive yellow color to Indian curries, has long been used in Ayurvedic and traditional Chinese medicine to aid digestion and liver function, relieve arthritis pain, and regulate menstruation.
Umckaloabo, orSouth African Geranium (Pelargonium sidoides), used in treating acute bronchitis.
Valerian (Valeriana officinalis) has been used since at least ancient Greece and Rome for sleep disorders and anxiety.
White willow (Salix alba) is a plant source of salicylic acid, a chemical related to aspirin, although more likely to cause stomach upset as a side effect than aspirin itself. Used from ancient times for the same uses as aspirin.
Yerba santa (Eriodictyon crassifolium) was used by the Chumash people to keep airways open for proper breathing.
Yohimbe (Pausinystalia yohimbe) has a long history of use in Africa as an aphrodisiac.