Table 2.

Pregabalin: pharmacokinetics and metabolism with comparison to gabapentin.

Structure	Gabapentin	Pregabalin
Tmax (h)	2–3	1
t1/2 (h)	5–7	5.5–6.7
Bioavailability	27–60%	>90%
Pharmacokinetics	Nonlinear (zero order)	Linear
Plasma protein binding	<3%	Assumed to be zero
Potency at the α2δ1 subunit	+	++
Metabolism	Nil	Very limited if any metabolism occurs. Some patients may have scant N-methylation occur
Renal excretion	100% unchanged	92–99% unchanged
Suggested dosing schedule	three or four times daily/	two or three times daily
Effective dose	1800–3600 mg/day	150–600 mg/day
Time to effective dose using recommended titrations	14 days	5–7 days
Dosing in renal impairment (creatinine clearance, ml/min)
≥60	1200–3600 mg/day	150–600 mg/day
30–60	600–1600 mg/day	75–300 mg/day (two or three times daily
15–30	300–900 mg/day	25–150 mg/day
<15	100–300 mg/day	25–75 mg/day (once daily)

This table has been modified from Table 3 in Toth [2012].