Nephrolithiasis in the communities of Northeast Thailand frequently presents with multiple chronic health complaints, i.e. myofascial pain, back pain, dyspepsia, arthralgia, headache, fatigue, frank paresthesia, dysuria and any of these aggravated by purine-rich food (PRF). We assessed the efficacy of Orthosiphon in treating subjects with at least two active symptoms and negative for urine white blood cells. Subjects were randomly allocated to two groups. Crude extract of Orthosiphon given in a capsule (equivalent to 1.6–1.8 g of dried leaves of Orthosiphon) two times a day to Group 1 (n = 36) and a placebo to Group 2 (n = 40) for 14 days. The medication for each subject was packed and its code kept secret until the data analysis. Both groups were asked not to consume any of 25 purin…