Find a Drug
Advanced Search

Professional

Glucophage

Clinical Pharmacology
font size

Clinical Pharmacology

In the presence of normal renal function, there are no differences between single- or multiple-dose pharmacokinetics of metformin between patients with type 2 diabetes and normal subjects (see Table 1), nor is there any accumulation of metformin in either group at usual clinical doses.

The pharmacokinetics of GLUCOPHAGE XR in patients with type 2 diabetes are comparable to those in healthy normal adults.

Renal Insufficiency

In patients with decreased renal function (based on measured creatinine clearance), the plasma and blood half-life of metformin is prolonged and the renal clearance is decreased in proportion to the decrease in creatinine clearance (see Table 1; also see WARNINGS).

Hepatic Insufficiency

No pharmacokinetic studies of metformin have been conducted in patients with hepatic insufficiency.

Geriatrics

Limited data from controlled pharmacokinetic studies of GLUCOPHAGE in healthy elderly subjects suggest that total plasma clearance of metformin is decreased, the half-life is prolonged, and Cmax is increased, compared to healthy young subjects. From these data, it appears that the change in metformin pharmacokinetics with aging is primarily accounted for by a change in renal function (see Table 1). GLUCOPHAGE (metformin hydrochloride tablets) and GLUCOPHAGE XR (metformin hydrochloride extended-release tablets) treatment should not be initiated in patients ≥ 80 years of age unless measurement of creatinine clearance demonstrates that renal function is not reduced (see WARNINGS and DOSAGE AND ADMINISTRATION).

Table 1: Select Mean (±S.D.) Metformin Pharmacokinetic Parameters
Following Single or Multiple Oral Doses of GLUCOPHAGE


Subject Groups: GLUCOPHAGE dosea
(number of subjects)
Cmaxb
(µg/mL)
Tmaxc
(hrs)
Renal
(mL/min)
Healthy, nondiabetic adults:
500 mg single dose (24) 1.03(±0.33) 2.75 (±0.81) 600 (±132)
850 mg single dose (74)d 1.60 (±0.38) 2.64 (±0.82) 552 (±139)
850 mg three times daily for 19 dosese (9) 2.01 (±0.42) 1.79 ( 0.94) 642 (±173)
Adults with type 2 diabetes:
850 mg single dose (23) 1.48 (±0.5) 3.32 (±1.08) 491 (±138)
850 mg three times daily for 19 dosese (9) 1.90 (±0.62) 2.01 (±1.22) 550 (±160)
Elderlyf, healthy nondiabetic adults:
850 mg single dose (12) 2.45 (±0.70) 2.71 (±1.05) 412 (±98)
Renal-impaired adults:
850 mg single dose
Mild (CLcrg 61-90 mL/min) (5) 1.86 (±0.52) 3.20 (±0.45) 384 (±122)
Moderate (CLcr 31-60 mL/min) (4) 4.12 (±1.83) 3.75 (±0.50) 108 (±57)
Severe (CLcr 10-30 mL/min) (6) 3.93 (±0.92) 4.01 (±1.10) 130 (±90)
a All doses given fasting except the first 18 doses of the multiple dose studies
b Peak plasma concentration
c Time to peak plasma concentration
d Combined results (average means) of five studies: mean age 32 years (range 23-59 years)
e Kinetic study done following dose 19, given fasting
f Elderly subjects, mean age 71 years (range 65-81 years)
g CLcr = creatinine clearance normalized to body surface area of 1.73 m²



Pediatrics
Brand Name: Glucophage
Generic Name: Metformin Hcl
Bookmark this page:

Diabetes

Find tips and advances in treatment.

WebMD Symptom Checker - Start Here Ringworm Slideshow: Watch and Learn

Living with an Insulin Pump Living with an Insulin Pump
After years of debilitating seizures, diabetic Melissa Jeffries regains control of her diabetes through the use of an insulin pump. See more WebMD Videos »