Cytotec
What is Cytotec?
A prostaglandin E1 analog called Cytotec (misoprostol) is prescribed to patients taking nonsteroidal anti-inflammatory drugs (NSAIDs) in order to prevent gastric ulcers. Additionally, Cytotec may be used to help a pregnant woman start the birthing process by inducing labor. Without consulting your doctor first, Cytotec should not be used for either scenario.
Other uses for Cytotec not covered in this medication guide are also possible.
Pharmacokinetics
Absorption:
Misoprostol is rapidly absorbed when taken orally. The absence of an appropriate assay prevents the determination of absolute bioavailability. About 80% of the drug is thought to be bioavailable.
Distribution:
Misoprostol acid is metabolized by the body and passes through the placenta. Following single and multiple 200 mcg oral doses, mean steady-state plasma concentrations in healthy women are around 3 ng/mL. Most misoprostol (99%) is bound to plasma proteins.
Metabolism:
Misoprostol acid is converted to misoprostol diols and other metabolites in the liver and intestine through oxidative N-demethylation, reduction of the carbonyl group, and O-dealkylation.
Elimination:
Mean plasma clearance after oral administration is roughly 0.6 L/hr/kg. The main method of elimination for the metabolites is through urinary excretion, which accounts for about 65% of the dose. The remaining 35% is accounted for by fecal excretion. Following both single and multiple oral doses, the mean terminal half-life in healthy women is 20 hours.
Drug interactions
The risk of gastrointestinal side effects is increased when misoprostol and NSAIDs are taken together. The response to misoprostol may be altered by concurrent use of additional medications that impact gastric acid secretion.
Inducers of cytochrome P450:
Misoprostol's efficacy may be impacted by the concurrent use of CYP3A4 inducers, such as carbamazepine, efavirenz, griseofulvin, nevirapine, phenytoin, and barbiturates, which may lower plasma concentrations of misoprostol acid. When taking misoprostol alongside CYP3A4 inducers, keep an eye out for any potential reductions in misoprostol's effectiveness and adjust the dosage as necessary.
Inhibitors of cytochrome P450:
When used with misoprostol, CYP3A4 inhibitors (such as macrolide antibiotics, azole antifungals, clarithromycin, erythromycin, fluconazole, HIV protease inhibitors, and ketoconazole) may raise plasma concentrations of misoprostol acid and raise the possibility of gastrointestinal side effects. When using CYP3A4 inhibitors concurrently, keep an eye out for any heightened gastrointestinal side effects and change the misoprostol dosage as necessary.
H2-receptor blockers:
Misoprostol's efficacy may be affected if H2-receptor antagonists like cimetidine, famotidine, nizatidine, and ranitidine are used concurrently, as they may lower the plasma concentrations of misoprostol acid. When misoprostol is administered alongside H2-receptor antagonists, keep an eye out for any potential loss of efficacy and adjust the dosage as necessary.
Anti-proton-pump drugs
Misoprostol and proton pump inhibitors used concurrently may result in lower plasma concentrations of misoprostol acid and possibly less risk its efficacy. When taking misoprostol alongside proton pump inhibitors, keep an eye out for any signs of diminished efficacy and adjust the dosage as necessary.
Anti-proton-pump drugs
Misoprostol's efficacy may be impacted by the concurrent use of proton pump inhibitors (such as omeprazole and lansoprazole), which may result in lower plasma concentrations of misoprostol acid. When taking misoprostol alongside proton pump inhibitors, keep an eye out for any signs of diminished efficacy and adjust the dosage as necessary.
Particular populations
hepatic dysfunction
In patients with mild to moderate hepatic impairment, exercise caution. Patients with severe hepatic impairment should not use.
Renal dysfunction:
In patients with mild to moderate renal impairment, exercise caution. Patients with severe renal impairment should not use.
Side effects
Diarrhea, abdominal pain, flatulence, and nausea are the side effects of misoprostol use that are most frequently reported (>3%). There have also been reports of anorexia, dyspepsia, vomiting, headaches, vertigo, weakness/fatigue, fever, and chills.
Dosage and Administration
Cytotec should be taken 200 mcg four times per day with food to reduce the risk of NSAID-induced gastric ulcers in patients at high risk. If a patient is unable to tolerate misoprostol four times per day, 200 mcg of the medication should be administered three times per day. 200 mcg twice daily should be used in place of three doses of misoprostol if the patient is unable to tolerate them.
The total daily dose shouldn't be more than 800 mcg if there are also indications of a duodenal ulcer in addition to a stomach ulcer.
The dosage is 200 mcg twice daily with food for patients at low risk to prevent NSAID-induced gastric ulcers.
For the treatment of an active duodenal ulcer, 400 mcg of Cytotec should be taken four times per day with food. 400 mcg of misoprostol should be administered three times a day if a patient cannot tolerate the drug four times a day. 400 mcg twice daily should be used in place of three doses of misoprostol if the patient is unable to tolerate them.
Overdose
A Cytotec overdose has no specific antidote. The best kind of treatment is supportive and symptomatic. If the patient presents within an hour of ingestion and there are no contraindications to its use, activated charcoal (60 to 100 g for adults, 1 to 2 g/kg for children) may be used to decontaminate the stomach.
Storage
The recommended storage range for tablets is 20°C to 25°C (68°F to 77°F), with excursions allowed to 15°C to 30°C (59°F to 86°F). shield from moisture and light.