Tonic water by mass), while the daily therapeutic dose of quinine is in the range of 500–1000 mg, and 10 mg/kg every eight hours for effective malaria prevention (2100 mg daily for a 70 kg adult). Still, it is often recommended as a relief for leg cramps but medical research suggests some care is needed in monitoring doses. Because of quinine's risks, the FDA cautions consumers against using "off-label" quinine drugs to treat leg cramps. Tonic water is often used as a drink mixer for cocktails, especially gin and tonic. Vodka tonic is also popular. Tonic water with lemon or lime flavor
Malaria furthest influence reaches into some temperate zones that have extreme seasonal changes. The disease has been associated with major negative economic effects on regions where it is widespread. During the late 19th and early 20th centuries, it was a major factor in the slow economic development of the American southern states. A comparison of average per capita GDP in 1995, adjusted for parity of purchasing power, between countries with malaria and countries without malaria gives a fivefold difference ($1,526 USD versus $8,268 USD). In the period 1965 to 1990, countries where malaria was common had an average per capita GDP