In the setting of rapidly improving or worsening renal function, calculations of CrCl are inaccurate. Dosing should be based on estimated renal function instead.
If improving renal function, actual CrCl is likely higher than calculated CrCl.
If worsening renal function, actual CrCl is likely lower than calculated CrCl.
CrCl ≥30 mL/min
500mg PO Q8h or 875mg PO Q12h
CrCl 10-29 mL/min
250-500mg PO Q12h
CrCl <10 mL/min
250-500mg PO Q24h
250-500mg PO Q24h (doses given on HD days should be given after HD)