Ethambutol Diazepam

The interaction of rifampicin with diazepam has been reviewed (54). The mean half-life of diazepam fell from 58 to 14 hours in seven patients who took isoniazid, rifampicin, and ethambutol (55). 

A study in 6 patients, newly diagnosed with tuberculosis and taking ethambutol 25 mg/kg, found that although some of the pharmacokinetic parameters of diazepam were different to those obtained in healthy control subjects not taking ethambutol, the differenees were not significant. There seems to be nothing in the literature to suggest that ethambutol interacts with other benzodiazepines. 

The mean half-life of diazepam was redueed from 58 to 14 hours and the elearanee was inereased fourfold in 7 patients with tuberculosis who were given daily doses of isoniazid 500 mg to 2.2 g, rifampicin 450 to 600 mg and ethambutol 25 mg/kg, when eompared with healthy control subjects. In 21 healthy subjeets rifampiein 600 mg or 1.2 g daily for 7 days inereased the elearanee of diazepam by about threefold. ... 

---