Asteraceae: Drug Interactions, Contraindications, And Precautions

Patient survey data from Canada, the U.S., and Australia show that one in five patients use prescription drugs concurrently with CAM. The inherent polypharmaceutical nature of complementary and alternative medicine increases the risk of adverse events if these complementary and alternative medicine either have pharmacological activity or interfere with drug metabolism. Since confirmed interactions are sporadic and based largely on case reports, advice to avoid certain drug-CAM combinations is based on known pharmacological and in vitro properties. Known Hypersensitivity to Asteraceae Cross-reactive sesquiterpene lactones are present in many, if not all, Asteraceae. Patients with known CAD from one plant may develop similar type IV reactions following contact with others. Affected patients are often advised to avoid contact with all Asteraceae, yet this advice is based on limited knowledge of cross-reactivity between relatively few members of this large family. Some authorities recommend avoiding Asteraceae-derived complementary and alternative medicine if, for example, the patient is known to have IgE-mediated inhalant allergy to ragweed. While a reasonable approach, this ignores a number of important facts: (1) Read more […]


ANTIANDROGENS (androgen antagonists) are a class of drugs that are hormone antagonists. Some drugs act directly to prevent the actions of the male sex hormone, testosterone, at receptors on its target tissues (e.g. cyproterone). Others act indirectly by preventing the formation of androgens by inhibiting the enzyme 5α-reductase (e.g. flutamide). Finally, some agents act indirectly by inhibiting the release of androgens (e.g. buserelin). Cyproterone is used in high doses as an ANTICANCER AGENT for cancer of the prostate gland. It is also used in relatively moderate doses, for the treatment of precocious puberty in males, and for hypersexuality or sexual deviation in men (in whom the drug causes a condition of reversible sterility through a reduction in the production of sperm and a decrease in libido). It works by being a derivative of progesterone with weak progestogenic activity. Thus it is a partial agonist at androgen receptors, competing with dihydrotestosterone for receptors in androgen-sensitive target tissues. By an effect on the hypothalamus it decreases the synthesis of gonadotrophins. It can also be used (orally at low dose, and in a preparation containing oestrogen) to treat acne, and excess body hair Read more […]