RANITIDINE TABLETS, USP DESCRIPTION: Ranitidine hydrochloride is a histamine H2-receptor
In these studies, patients treated with ranitidine reported a reduction in
No additional benefit in healing of esophagitis or in relief of heartburn was
were increased to at least twice the pretreatment levels in 6 of 12 subjects
antagonist. Chemically it is N-[2-[[[5-[(Dimethylamino)methyl]-2-
both daytime and nocturnal pain, and they also consumed less antacid than
seen with a ranitidine dose of 300 mg q.i.d.
receiving 100 mg q.i.d. intravenously for 7 days, and in 4 of 24 subjects
Maintenance of Healing of Erosive Esophagitis: In two multicenter, double-
receiving 50 mg q.i.d. intravenously for 5 days.
blind, randomized, placebo-controlled, 48-week trials conducted in patients
Musculoskeletal: Rare reports of arthralgias and myalgias.
Ranitidine HCl is a white to pale yellow, granular substance that is
Mean Daily Doses of Antacid
whose erosive esophagitis had been previously healed, ranitidine 150 mg
Hematologic: Blood count changes (leukopenia, granulocytopenia, and
soluble in water. It has a slightly bitter taste and sulfur like odor. It has the
b.i.d. was significantly more effective than placebo in maintaining healing
thrombocytopenia) have occurred in a few patients. These were usually
reversible. Rare cases of agranulocytosis, pancytopenia, sometimes with
INDICATIONS AND USAGE: Ranitidine tablets are indicated in:
marrow hypoplasia, and aplastic anemia and exceedingly rare cases of
1. Short-term treatment of active duodenal ulcer. Most patients heal within
acquired immune hemolytic anemia have been reported.
4 weeks. Studies available to date have not assessed the safety of ranitidine
Endocrine: Controlled studies in animals and man have shown no stimu-
in uncomplicated duodenal ulcer for periods of more than eight weeks.
lation of any pituitary hormone by ranitidine and no antiandrogenic activ-
Foreign studies have shown that patients heal equally well with 150 mg
2. Maintenance therapy for duodenal ulcer patients at reduced dosage after
ity, and cimetidine-induced gynecomastia and impotence in hypersecretory
b.i.d. and 300 mg h.s. (85% versus 84%, respectively) during a usual
healing of acute ulcers. No placebo-controlled comparative studies have been
patients have resolved when ranitidine has been substituted. However,
4-week course of therapy. If patients require extended therapy of 8 weeks,
carried out for periods of longer than 1 year.
occasional cases of gynecomastia, impotence, and loss of libido have been
the healing rate may be higher for 150 mg b.i.d. as compared to 300 mg
3. The treatment of pathological hypersecretory conditions (e.g., Zollinger-
reported in male patients receiving ranitidine, but the incidence did not dif-
h.s. (92% versus 87%, respectively).
Ellison syndrome and systemic mastocytosis).
fer from that in the general population.
Studies have been limited to short-term treatment of acute duodenal ulcer.
4. Short-term treatment of active, benign gastric ulcer. Most patients heal
Integumentary: Rash, including rare cases of erythema multiforme, and,
Patients whose ulcers healed during therapy had recurrences of ulcers at
within 6 weeks and the usefulness of further treatment has not been
Each tablet, for oral administration contains 168 mg or 336 mg of raniti-
demonstrated. Studies available to date have not assessed the safety of
Other: Rare cases of hypersensitivity reactions (e.g., bronchospasm, fever,
dine hydrochloride equivalent to 150 mg and 300 mg of ranitidine, respec-
Maintenance Therapy in Duodenal Ulcer: Ranitidine has been found to be
ranitidine in uncomplicated, benign gastric ulcer for periods of more than
rash, eosinophilia), anaphylaxis, angioneurotic edema, and small increases
tively. Inactive ingredients: D & C Red #30 Aluminum Lake, hydroxypropyl
effective as maintenance therapy for patients following healing of acute
cellulose, hydroxypropyl methylcellulose, magnesium stearate, microcrys-
duodenal ulcers. In two independent, double-blind, multicenter, controlled
5. Maintenance therapy for gastric ulcer patients at reduced dosage after
OVERDOSAGE: There has been limited experience with overdosage. Reported
talline cellulose, triethyl citrate, sodium starch glycolate, titanium dioxide and
trials, the number of duodenal ulcers observed was significantly less in
healing of acute ulcers. Placebo-controlled studies have been carried out
acute ingestions of up to 18 g orally have been associated with transient
flavoring. The 300 mg also contains: D & C Yellow #10 Aluminum Lake.
patients treated with ranitidine (150 mg h.s.) than in patients treated with
adverse effects similar to those encountered in normal clinical experience
CLINICAL PHARMACOLOGY: Ranitidine is a competitive, reversible inhibitor
6. Treatment of GERD. Symptomatic relief commonly occurs within 24
(see ADVERSE REACTIONS). In addition, abnormalities of gait and hypo-
of the action of histamine at the histamine H2-receptors, including recep-
hours after starting therapy with ranitidine 150 mg b.i.d.
tors on the gastric cells. Ranitidine does not lower serum Ca++ in hyper-
Duodenal Ulcer Prevalence
7. Treatment of endoscopically diagnosed erosive esophagitis. Symptomatic
When overdosage occurs, the usual measures to remove unabsorbed
calcemic states. Ranitidine is not an anticholinergic agent.
relief of heartburn commonly occurs within 24 hours of therapy initiation
material from the gastrointestinal tract, clinical monitoring, and supportive
Double-blind, Multicenter, Placebo-Controlled Trials
Absorption: Ranitidine is 50% absorbed after oral administration, com-
8. Maintenance of healing of erosive esophagitis. Placebo-controlled trials
Studies in dogs receiving dosages of ranitidine in excess of 225 mg/kg
pared to an intravenous (IV) injection with mean peak levels of 440 to 545
per day have shown muscular tremors, vomiting, and rapid respiration.
ng/mL occurring 2 to 3 hours after a 150 mg dose. Absorption is not sig-
Concomitant antacids should be given as needed for pain relief to patients
Single oral doses of 1,000 mg/kg in mice and rats were not lethal. Intra-
nificantly impaired by the administration of food or antacids. Propantheline
with active duodenal ulcer; active, benign gastric ulcer; hypersecretory
venous LD50 values in mice and rats were 77 and 83 mg/kg, respectively.
slightly delays and increases peak blood levels of ranitidine, probably by
states; GERD; and erosive esophagitis. DOSAGE AND ADMINISTRATION:
delaying gastric emptying and transit time. In one study, simultaneous
CONTRAINDICATIONS: Ranitidine tablets are contraindicated in patients Active Duodenal Ulcer: The current recommended adult oral dosage of
administration of high-potency antacid (150 mmol) in fasting subjects has
known to have hypersensitivity to the drug or any of the ingredients (see
ranitidine for duodenal ulcer is 150 mg of ranitidine twice daily. An alter-
been reported to decrease the absorption of ranitidine.
native dosage of 300 mg of ranitidine once daily after the evening meal or
Distribution: The volume of distribution is about 1.4 L/kg. Serum pro- PRECAUTIONS:
at bedtime can be used for patients in whom dosing convenience is impor-
tant. The advantages of one treatment regimen compared to the other in a
Metabolism: In humans, the N-oxide is the principle metabolite in the
1. Symptomatic response to therapy with ranitidine does not preclude the
particular patient population have yet to be demonstrated (see CLINICAL
urine; however, this amounts to <4% of the dose. Other metabolites are
PHARMACOLOGY, Clinical Trials: Active Duodenal Ulcer ). Smaller doses have
the S-oxide (1%) and the desmethyl ranitidine (1%). The remainder of the
2. Since ranitidine is excreted primarily by the kidney, dosage should be
been shown to be equally effective in inhibiting gastric acid secretion in US
administered dose is found in the stool. Studies in patients with hepatic
adjusted in patients with impaired renal function (see DOSAGE AND ADMIN-
studies, and several foreign trials have shown that 100 mg b.i.d. is as
dysfunction (compensated cirrhosis) indicate that there are minor, but clin-
* = p<0.05 (Ranitidine versus comparator).
ISTRATION). Caution should be observed in patients with hepatic dys-
ically insignificant, alterations in ranitidine half-life, distribution, clear-
function since ranitidine is metabolized in the liver.
Antacid should be given as needed for relief of pain (see CLINICAL
3. Rare reports suggest that ranitidine may precipitate acute porphyric
Excretion: The principal route of excretion is the urine, with approximately
attacks in patients with acute porphyria. Ranitidine should therefore be
Maintenance of Healing of Duodenal Ulcers: The current recommended
30% of the orally administered dose collected in the urine as unchanged
As with other H2-antagonists, the factors responsible for the significant
avoided in patients with a history of acute porphyria.
adult oral dosage is 150 mg of ranitidine at bedtime.
drug in 24 hours. Renal clearance is about 410 mL/min, indicating active
reduction in the prevalence of duodenal ulcers include prevention of recur-
Laboratory Tests: False-positive tests for urine protein with Multistix® Pathological Hypersecretory Conditions (such as Zollinger-Ellison
tubular excretion. The elimination half-life is 2.5 to 3 hours. Four patients
rence of ulcers, more rapid healing of ulcers that may occur during main-
may occur during ranitidine therapy, and therefore testing with sulfo-
syndrome): The current recommended adult oral dosage is 150 mg of
with clinically significant renal function impairment (creatinine clearance
ranitidine twice a day. In some patients it may be necessary to administer
25 to 35 mL/min) administered 50 mg of ranitidine intravenously had an
Gastric Ulcer: In a multicenter, double-blind, controlled, US study of endo-
Drug Interactions: Although ranitidine has been reported to bind weakly to
ranitidine 150 mg doses more frequently. Dosages should be adjusted to
average plasma half-life of 4.8 hour, a ranitidine clearance of 29 mL/min,
scopically diagnosed gastric ulcers, earlier healing was seen in the patients
cytochrome P-450 in vitro, recommended doses of the drug do not inhibit
individual patient needs, and should continue as long as clinically indicated.
and a volume of distribution of 1.76 L/kg. In general, these parameters
treated with ranitidine as shown in the following table:
the action of the cytochrome P-450-linked oxygenase enzymes in the liver.
Dosages up to 6 g/day have been employed in patients with severe disease.
appear to be altered in proportion to creatinine clearance (see DOSAGE AND
However, there have been isolated reports of drug interactions that suggest
Benign Gastric Ulcer: The current recommended adult oral dosage is Gastric Ulcer Patient Healing Rates
that ranitidine may affect the bioavailability of certain drugs by some
Pharmacodynamics: Serum concentrations necessary to inhibit 50% of stim-
mechanism as yet unidentified (e.g., a pH-dependent effect on absorption
Maintenance of Healing of Gastric Ulcers: The current recommended
ulated gastric acid secretion are estimated to be 36 to 94 ng/mL. Following
or a change in volume of distribution).
adult oral dosage is 150 mg of ranitidine at bedtime.
a single oral dose of 150 mg, serum concentrations of ranitidine are in this
Increased or decreased prothrombin times have been reported during
GERD: The current recommended adult oral dosage is 150 mg of ranitidine
range up to 12 hours. However, blood levels bear no consistent relationship
concurrent use of ranitidine and warfarin. However, in human pharmaco-
to dose or degree of acid inhibition.
kinetic studies with dosages of ranitidine up to 400 mg/day, no interaction
Erosive Esophagitis: The current recommended adult oral dosage is 150 mg Antisecretory Activity:
occurred; ranitidine had no effect on warfarin clearance or prothrombin time.
1. Effects on Acid Secretion: Ranitidine inhibits both daytime and noctur-
The possibility of an interaction with warfarin at dosages of ranitidine
Maintenance of Healing of Erosive Esophagitis: The current recom-
nal basal gastric acid secretions as well as gastric acid secretion stimulated
higher than 400 mg/day has not been investigated.
mended adult oral dosage is 150 mg of ranitidine twice a day.
by food, betazole, and pentagastrin, as shown in the following table:
In a ranitidine-triazolam drug-drug interaction study, triazolam plasma
Dosage Adjustment for Patients with Impaired Renal Function: On the basis
concentrations were higher during b.i.d. dosing of ranitidine than triazolam
of experience with a group of subjects with severely impaired renal func-
Effect of Oral Ranitidine on Gastric Acid Secretion
given alone. The mean area under the triazolam concentration-time curve
tion treated with ranitidine, the recommended dosage in patients with a
(AUC) values, in 18 to 60 year old subjects were 10% and 28% higher fol-
creatinine clearance <50 mL/min is 150 mg of ranitidine every 24 hours.
* All patients were permitted p.r.n. antacids for relief of pain.
lowing administration of 75 mg and 150 mg ranitidine tablets, respec-
Should the patient’s condition require, the frequency of dosing may be
tively, than triazolam given alone. In subjects older than 60 years of age, the
increased to every 12 hours or even further with caution. Hemodialysis
mean AUC values were approximately 30% higher following administration
reduces the level of circulating ranitidine. Ideally, the dosing schedule
In this multicenter trial, significantly more patients treated with ranitidine
of 75 mg and 150 mg ranitidine tablets. It appears that there were no
should be adjusted so that the timing of a scheduled dose coincides with
changes in pharmacokinetics of triazolam and α-hydroxytriazolam, a major
Maintenance of Healing of Gastric Ulcers: In two multicenter, double-blind,
metabolite, and in their elimination. Reduced gastric acidity due to raniti-
HOW SUPPLIED: Ranitidine tablets USP, for oral administration, are sup-
randomized, placebo-controlled, 12-month trials conducted in patients
dine may have resulted in an increase in the availability of triazolam. The
whose gastric ulcers had been previously healed, ranitidine 150 mg h.s. was
clinical significance of this triazolam and ranitidine pharmacokinetic inter-
150 mg: round, off-white, unscored tablets, film-coated pink, debossed
significantly more effective than placebo in maintaining healing of gastric
GG 705 on one side and plain on the reverse side, in bottles of 60, 100, 500
Carcinogenesis, Mutagenesis, Impairment of Fertility: There was no
and 1000, and in unit dose packages of 100. Pathological Hypersecretory Conditions (such as Zollinger-Ellison syn-
indication of tumorigenic or carcinogenic effects in life-span studies in
300 mg: round, off-white, unscored tablets, film-coated orange, debossed
It appears that basal-, nocturnal-, and betazole-stimulated secretions are
drome): Ranitidine inhibits gastric acid secretion and reduces occurrence
mice and rats at dosages up to 2,000 mg/kg per day.
GG 706 on one side and plain on the reverse side, in bottles of 30, 250 and
most sensitive to inhibition by ranitidine, responding almost completely to
of diarrhea, anorexia, and pain in patients with pathological hypersecretion
Ranitidine was not mutagenic in standard bacterial tests (Salmonella,
1000, and in unit dose packages of 100.
doses of 100 mg or less, while pentagastrin- and food-stimulated secretions
associated with Zollinger-Ellison syndrome, systemic mastocytosis, and other
Escherichia coli) for mutagenicity at concentrations up to the maximum rec-
Store at controlled room temperature 150-300C (590-860F). Store in a dry
pathological hypersecretory conditions (e.g., postoperative, “short-gut’’
place, and protect from light. Replace cap securely after each opening.
2. Effects on Other Gastrointestinal Secretions:
syndrome, idiopathic). Use of ranitidine was followed by healing of ulcers
In a dominant lethal assay, a single oral dose of 1,000 mg/kg to male rats
Dispense in a tight, light-resistant container. Pepsin: Oral ranitidine does not affect pepsin secretion. Total pepsin out-
in 8 of 19 (42%) patients who were intractable to previous therapy.
was without effect on the outcome of two matings per week for the next
put is reduced in proportion to the decrease in volume of gastric juice. Gastroesophageal Reflux Disease (GERD): In two multicenter, double-
Intrinsic Factor: Oral ranitidine has no significant effect on pentagastrin-
blind, placebo-controlled, 6-week trials performed in the United States and
Pregnancy: Teratogenic Effects: Pregnancy Category B: Reproduction
stimulated intrinsic factor secretion.
Europe, ranitidine 150 mg b.i.d. was more effective than placebo for the relief
studies have been performed in rats and rabbits at doses up to 160 times
Serum Gastrin: Ranitidine has little or no effect on fasting or postpran-
of heartburn and other symptoms associated with GERD.
the human dose and have revealed no evidence of impaired fertility or
Ranitidine-treated patients consumed significantly less antacid than did
harm to the fetus due to ranitidine. There are, however, no adequate and
Other Pharmacologic Actions:
well-controlled studies in pregnant women. Because animal reproduction
a. Gastric bacterial flora — increase in nitrate-reducing organisms, sig-
The US trial indicated that ranitidine 150 mg b.i.d. significantly reduced
studies are not always predictive of human response, this drug should be
the frequency of heartburn attacks and severity of heartburn pain within 1
used during pregnancy only if clearly needed. b. Prolactin levels — no effect in recommended oral or intravenous (IV)
to 2 weeks after starting therapy. The improvement was maintained through-
Nursing Mothers: Ranitidine is secreted in human milk. Caution should be
dosage, but small, transient, dose-related increases in serum prolactin
out the 6-week trial period. Moreover, patient response rates demonstrated
exercised when ranitidine is administered to a nursing mother.
have been reported after IV bolus injections of 100 mg or more.
that the effect on heartburn extends through both the day and night time
Pediatric Use: Safety and effectiveness in pediatric patients have not been c. Other pituitary hormones — no effect on serum gonadotropins, TSH, or
GH. Possible impairment of vasopressin release.
In two additional US multicenter, double-blind, placebo-controlled,
Use in Elderly Patients: Ulcer healing rates in elderly patients (65 to 82 years d. No change in cortisol, aldosterone, androgen, or estrogen levels.
2-week trials, ranitidine 150 mg b.i.d. was shown to provide relief of heart-
of age) were no different from those in younger age-groups. The incidence
e. No antiandrogenic action.
burn pain within 24 hours of initiating therapy and a reduction in the fre-
rates for adverse events and laboratory abnormalities were also not differ-
f. No effect on count, motility, or morphology of sperm.
ent from those seen in other age-groups. Clinical Trials: Erosive Esophagitis: In two multicenter, double-blind, randomized, placebo-
ADVERSE REACTIONS: The following have been reported as events in Active Duodenal Ulcer: In a multicenter, double-blind, controlled, US study
controlled, 12-week trials performed in the United States, ranitidine 150 mg
clinical trials or in the routine management of patients treated with raniti-
of endoscopically diagnosed duodenal ulcers, earlier healing was seen in
q.i.d. was significantly more effective than placebo in healing endoscopi-
dine. The relationship to therapy with ranitidine has been unclear in many
the patients treated with ranitidine as shown in the following table:
cally diagnosed erosive esophagitis and in relieving associated heartburn.
cases. Headache, sometimes severe, seems to be related to administration
The erosive esophagitis healing rates were as follows:
Duodenal Ulcer Patient Healing Rates Central Nervous System: Rarely, malaise, dizziness, somnolence, insom- Erosive Esophagitis Patient Healing Rates
nia, and vertigo. Rare cases of reversible mental confusion, agitation,
depression, and hallucinations have been reported, predominantly in
severely ill elderly patients. Rare cases of reversible blurred vision sugges-
tive of a change in accommodation have been reported. Rare reports of
reversible involuntary motor disturbances have been received. Cardiovascular: As with other H2-blockers, rare reports of arrhythmias such
as tachycardia, bradycardia, atrioventricular block, and premature ventric-
Gastrointestinal: Constipation, diarrhea, nausea/vomiting, abdominal dis-
comfort/pain, and rare reports of pancreatitis. Hepatic: There have been occasional reports of hepatocellular, cholestatic, or mixed hepatitis, with or without jaundice. In such circumstances, rani-
*All patients were permitted p.r.n. antacids for relief of pain.
* All patients were permitted p.r.n. antacids for relief of pain.
tidine should be immediately discontinued. These events are usually
reversible, but in rare circumstances death has occurred. Rare cases ofhepatic failure have also been reported. In normal volunteers, SGPT values
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