Is cimetidine metabolized by the liver?

A 67 year old man with gastroesophageal reflux disease (GERD) was found to have abnormal liver tests 7 months after starting cimetidine (400 mg daily)….Key Points.

Medication: Cimetidine (200 mg daily)
Latency: 7 months initially, 2 weeks upon rechallenge
Recovery: ~10 weeks initially, 2 weeks upon rechallenge

What is cimetidine made of?

Cimetidine is a member of the class of guanidines that consists of guanidine carrying a methyl substituent at position 1, a cyano group at position 2 and a 2-{[(5-methyl-1H-imidazol-4-yl)methyl]sulfanyl}ethyl group at position 3. It is a H2-receptor antagonist that inhibits the production of acid in stomach.

What is the pharmacokinetics of cimetidine?

Distribution of cimetidine leads to extensive uptake into kidney, lung and muscle tissues. It distributes into the cerebrospinal fluid (CSF) at a ratio of 0.1 to 0.2 compared with plasma. The mean saliva to plasma ratio is 0.2 (range 0.1–0.55).

How long does it take for cimetidine to leave your system?

The elimination half-life is about 2-3 hours. Cimetidine is eliminated primarily by the kidneys, and 60% or more may appear in the urine unchanged; much of the rest is oxidation products.

Are AST and ALT liver enzymes?

ALT is an enzyme found in the liver that helps convert proteins into energy for the liver cells. When the liver is damaged, ALT is released into the bloodstream and levels increase. Aspartate transaminase (AST). AST is an enzyme that helps metabolize amino acids.

Is cimetidine a calcium channel blocker?

Cimetidine increases plasma levels of some calcium-channel blockers by inhibiting their metabolism. Cimetidine increases plasma levels (notably pethidine) by inhibiting metabolism. Cimetidine increases plasma levels by inhibiting cytochrome P450-dependent metabolism.

What is the formula of cimetidine?

C10H16N6SCimetidine / Formula

What class of drug is cimetidine?

Cimetidine is in a class of medications called H2 blockers. It decreases the amount of acid made in the stomach.

Where is cimetidine absorbed?

Thus, it is suggested that cimetidine is completely absorbed in the duodenum and ileum during its passage through these intestinal sites, but at the jejunum an unabsorbed fraction of cimetidine passes to the ileum, where it is absorbed completely.

How is cimetidine absorbed?

Pharmacokinetics. Cimetidine is rapidly absorbed, and 70% of a given dose is bioavailable. Absorption can be slowed by the presence of food in the stomach. The mean absorption time for ranitidine was reported as approximately 1 h, and absorption was not impaired by the presence of food in the stomach.

Why cimetidine was removed from the market?

FDA seeks withdrawal of heartburn drugs due to new carcinogen concerns.

What happens if you take too much cimetidine?

Headache, dizziness, drowsiness, or diarrhea may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

How is cimetidine metabolized in the body?

It is metabolized in the liver into cimetidine sulfoxide, hydroxycimetidine, and guanyl urea cimetidine. The major metabolite of cimetidine is the sulfoxide, which accounts for about 30% of excreted material. Cimetidine is rapidly eliminated, with an elimination half-life of 123 minutes, or about 2 hours.

What is the molecular formula of cimetidine?

Cimetidine PubChem CID 2756 Structure Find Similar Structures Chemical Safety Laboratory Chemical Safety Summary (LCSS Molecular Formula C10H16N6S Synonyms cimetidine 51481-61-9 Tagamet Eureceptor

What is the oral bioavailability of cimetidine?

The oral bioavailability of cimetidine is 60 to 70%. The onset of action of cimetidine when taken orally is 30 minutes, and peak levels occur within 1 to 3 hours. Cimetidine is widely distributed throughout all tissues.

What is the affinity of metribolone and cimetidine?

However, the affinity of cimetidine for the AR is very weak; in one study, it showed only 0.00084% of the affinity of the anabolic steroid metribolone (100%) for the human AR (K i = 140 μM and 1.18 nM, respectively).