PRESCRIBING INFORMATIONRanitidine Tablets USP, 150 mg and 300 mg
DESCRIPTION
CLINICAL PHARMACOLOGY
Pharmacokinetics:
| Gastric or duodenal ulcer(3.5 to 16 years) | 12 | Tablets(1 to 2 mg/kg) | 54 to 492 | 2.0 |
| Otherwise healthy requiring ranitidine(0.7 to 14 years, Single dose) | 10 | Syrup(2 mg/kg) | 244 | 1.61 |
| Otherwise healthy requiring ranitidine (0.7 to 14 years, Multiple dose) | 10 | Syrup(2 mg/kg) | 320 | 1.66 |
| Basal | Up to 4 | 99 | 95 | ||
| Nocturnal | Up to 13 | 95 | 96 | 92 | |
| Betazole | Up to 3 | 97 | 99 | ||
| Pentagastin | Up to 5 | 58 | 72 | 72 | 80 |
| Meal | Up to 3 | 73 | 79 | 95 |
| Outpatients | 195 | 69/182(38%) † | 188 | 31/164(19%) |
| Week 2 | ||||
| Week 4 | 137/187(73%) † | 76/168(45%) | ||
| Ranitidine | 0.06 | 0.71 |
| Placebo | 0.71 | 1.43 |
| USA | RAN | 20%* | 24%* | 35%* | 138 |
| PLC | 44% | 54% | 59% | 139 | |
| Foreign | RAN | 12%* | 21%* | 28%* | 174 |
| PLC | 56% | 64% | 68% | 165 |
| Outpatients | 92 | 16/83(19%) | 94 | 10/83(12%) |
| Week 2 | ||||
| Week 6 | 50/73(68%)† | 35/69(51%) | ||
| Week 4 | 43/198 (22%) | 96/206 (47%) † |
| Week 8 | 63/176 (36%) | 142/200 (71%) † |
| Week 12 | 92/159 (58%) | 162/192 (84%) † |
- Gastric bacterial flora—increase in nitrate-reducing organisms, significance not known.
- Prolactin levels—no effect in recommended oral or IV dosage, but small, transient, dose-related increases in serum prolactin have been reported after IV bolus injections of 100 mg or more.
- Other pituitary hormones—no effect on serum gonadotropins, TSH, or GH. Possible impairment of vasopressin release.
- No change in cortisol, aldosterone, androgen, or estrogen levels.
- No antiandrogenic action.
- No effect on count, motility, or morphology of sperm.
INDICATIONS AND USAGE
- Short-term treatment of active duodenal ulcer. Most patients heal within 4 weeks. Studies available to date have not assessed the safety of ranitidine in uncomplicated duodenal ulcer for periods of more than 8 weeks.
- Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of acute ulcers. No placebo-controlled comparative studies have been carried out for periods of longer than 1 year.
- The treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome and systemic mastocytosis).
- Short-term treatment of active, benign gastric ulcer. Most patients heal within 6 weeks and the usefulness of further treatment has not been demonstrated. Studies available to date have not assessed the safety of ranitidine in uncomplicated, benign gastric ulcer for periods of more than 6 weeks.
- Maintenance therapy for gastric ulcer patients at reduced dosage after healing of acute ulcers. Placebo-controlled studies have been carried out for 1 year.
- Treatment of GERD. Symptomatic relief commonly occurs within 24 hours after starting therapy with ranitidine 150 mg twice daily.
- Treatment of endoscopically diagnosed erosive esophagitis. Symptomatic relief of heartburn commonly occurs within 24 hours of therapy initiation with ranitidine 150 mg 4 times daily.
- Maintenance of healing of erosive esophagitis. Placebo-controlled trials have been carried out for 48 weeks.
CONTRAINDICATIONS
PRECAUTIONS
- Symptomatic response to therapy with ranitidine does not preclude the presence of gastric malignancy.
- Since ranitidine is excreted primarily by the kidney, dosage should be adjusted in patients with impaired renal function (see DOSAGE AND ADMINISTRATION). Caution should be observed in patients with hepatic dysfunction since ranitidine is metabolized in the liver.
- Rare reports suggest that ranitidine may precipitate acute porphyric attacks in patients with acute porphyria. Ranitidine should therefore be avoided in patients with a history of acute porphyria.