Hepatic Metabolism

Hepatic metabolism is the principal method of clearance for the tricyclic and tetracyclic compounds. Only a small portion of drug is eliminated by the kidney. Rates of hepatic metabolism vary widely from person to person, resulting in dramatic differences in steady-state plasma concentrations. Elimination half-lives for most of the tricyclic and tetracyclic compounds average about 24 hours or longer; thus, the drugs can be given once a day (Table 12-2). Amoxapine has a shorter half-life than the other tricyclics and is an exception.

TABLE 12-2. Dosage, clearance, and apparent therapeutic plasma concentrations of tricyclics and tetracyclics

Plasma Therapeutic

Drug Half-life Clearance Dosage range Plasma level

Plasma

Therapeutic

Drug Half-life (hours)

Tertiary tricyclics

Amitriptyline 5-45

Clomipramine 15-60

Doxepin 10-25

Imipramine 5-30

Trimipramine 15-40

Secondary tricyclics

Desipramine 10-30

Nortriptyline 20-55

Protriptyline 55-200 Tetracyclics

Amoxapine 5-10

Maprotiline 25-50

Clearance (L/hour)

Nicotine Support Superstar

Nicotine Support Superstar

Stop Nicotine Addiction Is Not Easy, But You Can Do It. Discover How To Have The Best Chance Of Quitting Nicotine And Dramatically Improve Your Quality Of Your Life Today. Finally You Can Fully Equip Yourself With These Must know Blue Print To Stop Nicotine Addiction And Live An Exciting Life You Deserve!

Get My Free Ebook


Post a comment