Toe cramps, like their more painful analogues in the calf, are associated with conditions other than aging as well. Yet despite their prevalence, few successful remedies have been found. "A lot of treatments have been used in the past," says Stanford University neurologist Yuen So. Among the oldest is quinine, the malaria-fighting drug that gives tonic water its bite. A tablet before bed can have a small effect on nighttime cramping—however, the FDA now discourages its use because of rare, but very serious, side effects, such as low blood platelet counts. Other options include vitamin B complex and magnesium, but nothing has been proven effective. "There isn't a gold standard out there," So says.