Zantac Maximum Strength 150 MG Oral Tablet
Generic Name: RANITIDINE HYDROCHLORIDE
Brand Name: ZANTAC
- Substance Name(s):
- RANITIDINE HYDROCHLORIDE
DRUG INTERACTIONS
Drug Interactions: Ranitidine has been reported to affect the bioavailability of other drugs through several different mechanisms such as competition for renal tubular secretion, alteration of gastric pH, and inhibition of cytochrome P450 enzymes.
Procainamide: Ranitidine, a substrate of the renal organic cation transport system, may affect the clearance of other drugs eliminated by this route.
High doses of ranitidine (e.g., such as those used in the treatment of Zollinger-Ellison syndrome) have been shown to reduce the renal excretion of procainamide and N-acetylprocainamide resulting in increased plasma levels of these drugs.
Although this interaction is unlikely to be clinically relevant at usual ranitidine doses, it may be prudent to monitor for procainamide toxicity when administered with oral ranitidine at a dose exceeding 300 mg per day.
Warfarin: There have been reports of altered prothrombin time among patients on concomitant warfarin and ranitidine therapy.
Due to the narrow therapeutic index, close monitoring of increased or decreased prothrombin time is recommended during concurrent treatment with ranitidine.
Ranitidine may alter the absorption of drugs in which gastric pH is an important determinant of bioavailability.
This can result in either an increase in absorption (e.g., triazolam, midazolam, glipizide) or a decrease in absorption (e.g., ketoconazole, atazanavir, delavirdine, gefitinib).
Appropriate clinical monitoring is recommended.
Atazanavir: Atazanavir absorption may be impaired based on known interactions with other agents that increase gastric pH.
Use with caution.
See atazanavir label for specific recommendations.
Delavirdine: Delavirdine absorption may be impaired based on known interactions with other agents that increase gastric pH.
Chronic use of H2-receptor antagonists with delavirdine is not recommended.
Gefitinib: Gefitinib exposure was reduced by 44% with the coadministration of ranitidine and sodium bicarbonate (dosed to maintain gastric pH above 5.0).
Use with caution.
Glipizide: In diabetic patients, glipizide exposure was increased by 34% following a single 150-mg dose of oral ranitidine.
Use appropriate clinical monitoring when initiating or discontinuing ranitidine.
Ketoconazole: Oral ketoconazole exposure was reduced by up to 95% when oral ranitidine was coadministered in a regimen to maintain a gastric pH of 6 or above.
The degree of interaction with usual dose of ranitidine (150 mg twice daily) is unknown.
Midazolam: Oral midazolam exposure in 5 healthy volunteers was increased by up to 65% when administered with oral ranitidine at a dose of 150 mg twice daily.
However, in another interaction trial in 8 volunteers receiving IV midazolam, a 300-mg oral dose of ranitidine increased midazolam exposure by about 9%.
Monitor patients for excessive or prolonged sedation when ranitidine is coadministered with oral midazolam.
Triazolam: Triazolam exposure in healthy volunteers was increased by approximately 30% when administered with oral ranitidine at a dose of 150 mg twice daily.
Monitor patients for excessive or prolonged sedation.
OVERDOSAGE
There has been limited experience with overdosage.
Reported acute ingestions of up to 18 g orally have been associated with transient adverse effects similar to those encountered in normal clinical experience (see ADVERSE REACTIONS).
In addition, abnormalities of gait and hypotension have been reported.
When overdosage occurs, the usual measures to remove unabsorbed material from the gastrointestinal tract, clinical monitoring, and supportive therapy should be employed.
Studies in dogs receiving dosages of ZANTAC in excess of 225 mg/kg/day have shown muscular tremors, vomiting, and rapid respiration.
Single oral doses of 1,000 mg/kg in mice and rats were not lethal.
Intravenous LD50 values in mice and rats were 77 and 83 mg/kg, respectively.
DESCRIPTION
The active ingredient in ZANTAC 150 Tablets and ZANTAC 300 Tablets is ranitidine hydrochloride (HCl), USP, a histamine H2-receptor antagonist.
Chemically it is N[2-[[[5-[(dimethylamino)methyl]-2-furanyl]methyl]thio]ethyl]-N′-methyl-2-nitro-1,1-ethenediamine, HCl.
It has the following structure: The empirical formula is C13H22N4O3S•HCl, representing a molecular weight of 350.87.
Ranitidine HCl is a white to pale yellow granular substance that is soluble in water.
It has a slightly bitter taste and sulfur-like odor.
Each ZANTAC 150 Tablet for oral administration contains 168 mg of ranitidine HCl equivalent to 150 mg of ranitidine.
Each tablet also contains the inactive ingredients FD&C Yellow No.
6 Aluminum Lake, hypromellose, magnesium stearate, microcrystalline cellulose, titanium dioxide, triacetin, and yellow iron oxide.
Each ZANTAC 300 Tablet for oral administration contains 336 mg of ranitidine HCl equivalent to 300 mg of ranitidine.
Each tablet also contains the inactive ingredients croscarmellose sodium, D&C Yellow No.
10 Aluminum Lake, hypromellose, magnesium stearate, microcrystalline cellulose, titanium dioxide, and triacetin.
ranitidine HCl molecular structure
CLINICAL STUDIES
Clinical Trials: Active Duodenal Ulcer: In a multicenter, double-blind, controlled, US trial of endoscopically diagnosed duodenal ulcers, earlier healing was seen in the patients treated with ZANTAC as shown in Table 3.
Table 3.
Duodenal Ulcer Patient Healing Rates ZANTACa Placeboa Number Entered Healed/ Evaluable Number Entered Healed/ Evaluable Outpatients Week 2 69/182 (38%)b 31/164 (19%) 195 188 Week 4 137/187 (73%)b 76/168 (45%) a All patients were permitted antacids as needed for relief of pain.
b P<0.0001.
In these trials, patients treated with ZANTAC reported a reduction in both daytime and nocturnal pain, and they also consumed less antacid than the placebo-treated patients.
Table 4.
Mean Daily Doses of Antacid Ulcer Healed Ulcer Not Healed ZANTAC 0.06 0.71 Placebo 0.71 1.43 Foreign trials have shown that patients heal equally well with 150 mg twice daily and 300 mg at bedtime (85% versus 84%, respectively) during a usual 4-week course of therapy.
If patients require extended therapy of 8 weeks, the healing rate may be higher for 150 mg twice daily as compared with 300 mg at bedtime (92% versus 87%, respectively).
Trials have been limited to short-term treatment of acute duodenal ulcer.
Patients whose ulcers healed during therapy had recurrences of ulcers at the usual rates.
Maintenance Therapy in Duodenal Ulcer: Ranitidine has been found to be effective as maintenance therapy for patients following healing of acute duodenal ulcers.
In 2 independent, double-blind, multicenter, controlled trials, the number of duodenal ulcers observed was significantly less in patients treated with ZANTAC (150 mg at bedtime) than in patients treated with placebo over a 12-month period.
Table 5.
Duodenal Ulcer Prevalence Double-Blind, Multicenter, Placebo-Controlled Trials MulticenterTrial Drug Duodenal Ulcer Prevalence No.
of Patients 0-4 Months 0-8 Months 0-12 Months USA RAN 20%a 24% 35%a 138 PLC 44% 54% 59% 139 Foreign RAN 12%a 21%a 28%a 174 PLC 56% 64% 68% 165 % = Life table estimate.
a = P<0.05 (ZANTAC versus comparator).
RAN = ranitidine (ZANTAC).
PLC = placebo.
As with other H2-antagonists, the factors responsible for the significant reduction in the prevalence of duodenal ulcers include prevention of recurrence of ulcers, more rapid healing of ulcers that may occur during maintenance therapy, or both.
Gastric Ulcer: In a multicenter, double-blind, controlled, US trial of endoscopically diagnosed gastric ulcers, earlier healing was seen in the patients treated with ZANTAC as shown in Table 6.
Table 6.
Gastric Ulcer Patient Healing Rates ZANTACa Placeboa Number Entered Healed/ Evaluable Number Entered Healed/ Evaluable Outpatients Week 2 16/83 (19%) 10/83 (12%) 92 94 Week 6 50/73 (68%)b 35/69 (51%) a All patients were permitted antacids as needed for relief of pain.
b P = 0.009.
In this multicenter trial, significantly more patients treated with ZANTAC became pain free during therapy.
Maintenance of Healing of Gastric Ulcers: In 2 multicenter, double-blind, randomized, placebo-controlled, 12-month trials conducted in patients whose gastric ulcers had been previously healed, ZANTAC 150 mg at bedtime was significantly more effective than placebo in maintaining healing of gastric ulcers.
Pathological Hypersecretory Conditions (such as Zollinger-Ellison syndrome): ZANTAC inhibits gastric acid secretion and reduces occurrence of diarrhea, anorexia, and pain in patients with pathological hypersecretion associated with Zollinger-Ellison syndrome, systemic mastocytosis, and other pathological hypersecretory conditions (e.g., postoperative, “short-gut” syndrome, idiopathic).
Use of ZANTAC was followed by healing of ulcers in 8 of 19 (42%) patients who were intractable to previous therapy.
Gastroesophageal Reflux Disease (GERD): In 2 multicenter, double-blind, placebo-controlled, 6-week trials performed in the United States and Europe, ZANTAC 150 mg twice daily was more effective than placebo for the relief of heartburn and other symptoms associated with GERD.
Ranitidine-treated patients consumed significantly less antacid than did placebo-treated patients.
The US trial indicated that ZANTAC 150 mg twice daily significantly reduced the frequency of heartburn attacks and severity of heartburn pain within 1 to 2 weeks after starting therapy.
The improvement was maintained throughout the 6-week trial period.
Moreover, patient response rates demonstrated that the effect on heartburn extends through both the day and night time periods.
In 2 additional US multicenter, double-blind, placebo-controlled, 2-week trials, ZANTAC 150 mg twice daily was shown to provide relief of heartburn pain within 24 hours of initiating therapy and a reduction in the frequency of severity of heartburn.
Erosive Esophagitis: In 2 multicenter, double-blind, randomized, placebo-controlled, 12-week trials performed in the United States, ZANTAC 150 mg 4 times daily was significantly more effective than placebo in healing endoscopically diagnosed erosive esophagitis and in relieving associated heartburn.
The erosive esophagitis healing rates were as follows: Table 7.
Erosive Esophagitis Patient Healing Rates Healed/Evaluable Placeboa n = 229 ZANTAC 150 mg 4 times dailya n = 215 Week 4 43/198 (22%) 96/206 (47%)b Week 8 63/176 (36%) 142/200 (71%)b Week 12 92/159 (58%) 162/192 (84%)b a All patients were permitted antacids as needed for relief of pain.
b P<0.001 versus placebo.
No additional benefit in healing of esophagitis or in relief of heartburn was seen with a ranitidine dose of 300 mg 4 times daily.
Maintenance of Healing of Erosive Esophagitis: In 2 multicenter, double-blind, randomized, placebo-controlled, 48-week trials conducted in patients whose erosive esophagitis had been previously healed, ZANTAC 150 mg twice daily was significantly more effective than placebo in maintaining healing of erosive esophagitis.
HOW SUPPLIED
ZANTAC 150 Tablets (ranitidine HCl equivalent to 150 mg of ranitidine) are peach, film-coated, 5-sided tablets embossed with “ZANTAC 150” on one side and “Glaxo” on the other.
They are available in bottles of 60 (NDC 0173-0344-42) tablets.
ZANTAC 300 Tablets (ranitidine HCl equivalent to 300 mg of ranitidine) are yellow, film-coated, capsule-shaped tablets embossed with “ZANTAC 300” on one side and “Glaxo” on the other.
They are available in bottles of 30 (NDC 0173-0393-40) tablets.
Store between 15° and 30°C (59° and 86°F) in a dry place.
Protect from light.
Replace cap securely after each opening.
GlaxoSmithKline Research Triangle Park, NC 27709 ZANTAC is a registered trademark of Boehringer Ingelheim Pharmaceuticals, Inc., used under license.
MULTISTIX is a trademark of its respective owner and is not a trademark of the GSK group of companies.
The maker of this brand is not affiliated with and does not endorse the GSK group of companies or its products.
©2016 the GSK group of companies.
All rights reserved.
August 2016 ZNT:9PI
GERIATRIC USE
Geriatric Use: Of the total number of subjects enrolled in US and foreign controlled clinical trials of oral formulations of ZANTAC, for which there were subgroup analyses, 4,197 were aged 65 and older, while 899 were aged 75 and older.
No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.
This drug is known to be substantially excreted by the kidney and the risk of toxic reactions to this drug may be greater in patients with impaired renal function.
Because elderly patients are more likely to have decreased renal function, caution should be exercised in dose selection, and it may be useful to monitor renal function (see CLINICAL PHARMACOLOGY: Pharmacokinetics: Geriatrics and DOSAGE AND ADMINISTRATION: Dosage Adjustment for Patients with Impaired Renal Function).
INDICATIONS AND USAGE
ZANTAC is indicated in: 1.Short-term treatment of active duodenal ulcer.
Most patients heal within 4 weeks.
Trials available to date have not assessed the safety of ranitidine in uncomplicated duodenal ulcer for periods of more than 8 weeks.
2.Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of acute ulcers.
No placebo-controlled comparative trials have been carried out for periods of longer than 1 year.
3.The treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome and systemic mastocytosis).
4.Short-term treatment of active, benign gastric ulcer.
Most patients heal within 6 weeks and the usefulness of further treatment has not been demonstrated.
Trials available to date have not assessed the safety of ranitidine in uncomplicated, benign gastric ulcer for periods of more than 6 weeks.
5.Maintenance therapy for gastric ulcer patients at reduced dosage after healing of acute ulcers.
Placebo-controlled trials have been carried out for 1 year.
6.Treatment of GERD.
Symptomatic relief commonly occurs within 24 hours after starting therapy with ZANTAC 150 mg twice daily.
7.Treatment of endoscopically diagnosed erosive esophagitis.
Symptomatic relief of heartburn commonly occurs within 24 hours of therapy initiation with ZANTAC 150 mg 4 times daily.
8.Maintenance of healing of erosive esophagitis.
Placebo-controlled trials have been carried out for 48 weeks.
Concomitant antacids should be given as needed for pain relief to patients with active duodenal ulcer; active, benign gastric ulcer; hypersecretory states; GERD; and erosive esophagitis.
PEDIATRIC USE
Pediatric Use: The safety and effectiveness of ZANTAC have been established in the age-group of 1 month to 16 years for the treatment of duodenal and gastric ulcers, gastroesophageal reflux disease and erosive esophagitis, and the maintenance of healed duodenal and gastric ulcer.
Use of ZANTAC in this age-group is supported by adequate and well-controlled trials in adults, as well as additional pharmacokinetic data in pediatric patients and an analysis of the published literature (see CLINICAL PHARMACOLOGY: Pediatrics and DOSAGE AND ADMINISTRATION: Pediatric Use).
Safety and effectiveness in pediatric patients for the treatment of pathological hypersecretory conditions or the maintenance of healing of erosive esophagitis have not been established.
Safety and effectiveness in neonates (aged younger than 1 month) have not been established (see CLINICAL PHARMACOLOGY: Pediatrics).
PREGNANCY
Pregnancy: Teratogenic Effects: Pregnancy Category B.
Reproduction studies have been performed in rats and rabbits at doses up to 160 times the human dose and have revealed no evidence of impaired fertility or harm to the fetus due to ZANTAC.
There are, however, no adequate and well-controlled studies in pregnant women.
Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
NUSRING MOTHERS
Nursing Mothers: Ranitidine is secreted in human milk.
Caution should be exercised when ZANTAC is administered to a nursing mother.
DOSAGE AND ADMINISTRATION
Active Duodenal Ulcer: The current recommended adult oral dosage of ZANTAC for duodenal ulcer is 150 mg twice daily.
An alternative dosage of 300 mg once daily after the evening meal or at bedtime can be used for patients in whom dosing convenience is important.
The advantages of one treatment regimen compared with the other in a particular patient population have yet to be demonstrated (see Clinical Trials: Active Duodenal Ulcer).
Smaller doses have been shown to be equally effective in inhibiting gastric acid secretion in US trials, and several foreign trials have shown that 100 mg twice daily is as effective as the 150-mg dose.
Antacid should be given as needed for relief of pain (see CLINICAL PHARMACOLOGY: Pharmacokinetics).
Maintenance of Healing of Duodenal Ulcers: The current recommended adult oral dosage is 150 mg at bedtime.
Pathological Hypersecretory Conditions (such as Zollinger-Ellison syndrome): The current recommended adult oral dosage is 150 mg twice daily.
In some patients it may be necessary to administer ZANTAC 150-mg doses more frequently.
Dosages should be adjusted to individual patient needs, and should continue as long as clinically indicated.
Dosages up to 6 g/day have been employed in patients with severe disease.
Benign Gastric Ulcer: The current recommended adult oral dosage is 150 mg twice daily.
Maintenance of Healing of Gastric Ulcers: The current recommended adult oral dosage is 150 mg at bedtime.
GERD: The current recommended adult oral dosage is 150 mg twice daily.
Erosive Esophagitis: The current recommended adult oral dosage is 150 mg 4 times daily.
Maintenance of Healing of Erosive Esophagitis: The current recommended adult oral dosage is 150 mg twice daily.
Pediatric Use: The safety and effectiveness of ZANTAC have been established in the age-group of 1 month to 16 years.
There is insufficient information about the pharmacokinetics of ZANTAC in neonatal patients (aged younger than 1 month) to make dosing recommendations.
The following 3 subsections provide dosing information for each of the pediatric indications.
Treatment of Duodenal and Gastric Ulcers: The recommended oral dose for the treatment of active duodenal and gastric ulcers is 2 to 4 mg/kg twice daily to a maximum of 300 mg/day.
This recommendation is derived from adult clinical trials and pharmacokinetic data in pediatric patients.
Maintenance of Healing of Duodenal and Gastric Ulcers: The recommended oral dose for the maintenance of healing of duodenal and gastric ulcers is 2 to 4 mg/kg once daily to a maximum of 150 mg/day.
This recommendation is derived from adult clinical trials and pharmacokinetic data in pediatric patients.
Treatment of GERD and Erosive Esophagitis: Although limited data exist for these conditions in pediatric patients, published literature supports a dosage of 5 to 10 mg/kg/day, usually given as 2 divided doses.
Dosage Adjustment for Patients with Impaired Renal Function: On the basis of experience with a group of subjects with severely impaired renal function treated with ZANTAC, the recommended dosage in patients with a creatinine clearance <50 mL/min is 150 mg every 24 hours.
Should the patient’s condition require, the frequency of dosing may be increased to every 12 hours or even further with caution.
Hemodialysis reduces the level of circulating ranitidine.
Ideally, the dosing schedule should be adjusted so that the timing of a scheduled dose coincides with the end of hemodialysis.
Elderly patients are more likely to have decreased renal function, therefore caution should be exercised in dose selection, and it may be useful to monitor renal function (see CLINICAL PHARMACOLOGY: Pharmacokinetics: Geriatrics and PRECAUTIONS: Geriatric Use).