Ačkoliv jsou dostupné jen velmi omezené údaje, pacienti se závažnou dysfunkcí ledvin (clearance kreatininu = < 20 ml/ min) nebo pacienti na dialýze by mohli začít léčbu stejnou dávkou 400 mg.
Although very limited information is available, patients with severe renal dysfunction (creatinine clearance = < 20 ml/ min) or on dialysis could also start at the same dose of 400 mg.