– Methotrexate was initially used to treat malignancy. Many years later it was discovered to treat, at a much lower dose, several types of arthritic conditions.
– Quinine is well known as a treatment for malaria. It has given rise to new quinine-like drug, hydroxychloroquine, known as Plaquenil, to treat rheumatoid arthritis.
– When aspirin was discovered in 1897 it was in use at a high dose to treat inflammation, but eighteen years later doctors found that aspirin at a low dose has no more anti-inflammatory action but was as blood thinner.
– Minoxidil in pills is used to treat high blood pressure, and in lotion to help growing hair on the scalp.
– Ibuprofen and other anti-inflammatory drugs have found a new indication in treating premenstruel syndrome (PMS).