Brands, Medical Use, Clinical Data
Drug Category
- Anti-ulcer Agents
- Proton-pump Inhibitors
Dosage Forms
Brands / Synonyms
Pantoloc; Pantoprazol [Inn-Spanish]; Pantoprazole Na; Pantoprazole Sodium; Pantoprazole [Usan:Ban:Inn]; Pantoprazolum [Inn-Latin]; Pantoprozole; Protonix; Protonix I.V.; Protonix Injection; Protonix IV
Indications
Short-term (up to 16 weeks) treatment of erosive esophagitis.
Pharmacology
Pantoprazole is a substituted benzimidazole indicated for the short-term treatment (up to 16 weeks) in the healing and symptomatic relief of erosive esophagitis. Pantoprazole is a proton pump inhibitor (PPI) that suppresses the final step in gastric acid production.
Mechanism of Action
Pantoprazole is a proton pump inhibitor (PPI) that suppresses the final step in gastric acid production by forming a covalent bond to two sites of the (H+,K+ )- ATPase enzyme system at the secretory surface of the gastric parietal cell. This effect is dose- related and leads to inhibition of both basal and stimulated gastric acid secretion irrespective of the stimulus.
Absorption
Pantoprazole is well absorbed; it undergoes little first-pass metabolism resulting in an absolute bioavailability of approximately 77%.
Toxicity
Not Available
Biotrnasformation / Drug Metabolism
Pantoprazole is extensively metabolized in the liver through the cytochrome P450 (CYP) system. The main metabolic pathway is demethylation, by CYP2C19, with subsequent sulfation; other metabolic pathways include oxidation by CYP3A4. There is no evidence that any of the pantoprazole metabolites have significant pharmacologic activity.
Contraindications
PROTONIX Delayed- Release Tablets are contraindicated in patients with known hypersensitivity to any component of
the formulation.
Drug Interactions
Pantoprazole is metabolized through the cytochrome P450 system, primarily the CYP2C19 and CYP3A4 isozymes, and
subsequently undergoes Phase II conjugation.
Based on studies evaluating possible interactions of pantoprazole with other drugs, no dosage adjustment is needed
with concomitant use of the following: theophylline, cisapride, antipyrine, caffeine, carbamazepine, diazepam (and
its active metabolite, desmethyldiazepam), diclofenac, naproxen, piroxicam, digoxin, ethanol, glyburide, an oral
contraceptive (levonorgestrel/ethinyl estradiol), metoprolol, nifedipine, phenytoin, warfarin, midazolam,
clarithromycin, metronidazole, or amoxicillin. Clinically relevant interactions of pantoprazole with other drugs with
the same metabolic pathways are not expected. Therefore, when coadministered with pantoprazole, adjustment of the
dosage of pantoprazole or of such drugs may not be necessary. There was also no interaction with concomitantly
administered antacids. There have been postmarketing reports of increased INR and prothrombin time in patients
receiving proton pump inhibitors, including pantoprazole, and warfarin concomitantly. Increases in INR and
prothrombin time may lead to abnormal bleeding and even death. Patients treated with proton pump inhibitors and
warfarin concomitantly should be monitored for increases in INR and prothrombin time.
Because of profound and long lasting inhibition of gastric acid secretion, pantoprazole may interfere with
absorption of drugs where gastric pH is an important determinant of their bioavailability (eg, ketoconazole,
ampicillin esters, and iron salts).
Laboratory Tests
There have been reports of false-positive urine screening tests for tetrahydrocannabinol (THC) in patients
receiving most proton pump inhibitors, including pantoprazole. An alternative confirmatory method should be
considered to verify positive results.
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