Verapamil is excreted in human milk. Because of the potential for adverse reactions in nursing infants from verapamil, nursing should be discontinued while verapamil is administered.
Safety and efficacy of verapamil hydrochloride extended-release tablets in pediatric patients below the age of 18 years have not been established.
In chronic animal toxicology studies, verapamil caused lenticular and/or suture line changes at 30 mg/kg/day or greater, and frank cataracts at 62.5 mg/kg/day or greater in the beagle dog but not in the rat. Development of cataracts due to verapamil has not been reported in man.
Serious adverse reactions are uncommon when verapamil therapy is initiated with upward dose titration within the recommended single and total daily dose. See WARNINGS for discussion of heart failure, hypotension, elevated liver enzymes, AV block, and rapid ventricular response. Reversible (upon discontinuation of verapamil) non-obstructive, paralytic ileus has been infrequently reported in association with the use of verapamil. The following reactions to orally administered verapamil occurred at rates greater than 1.0% or occurred at lower rates but appeared clearly drug-related in clinical trials in 4,954 patients:
|Hypotension||2.5%||AV Block-total(1°, 2°, 3°)||1.2%|
|CHF, Pulmonary Edema||1.8%||Flushing||0.6%|
|Elevated Liver Enzymes (see WARNINGS)|
In clinical trials related to the control of ventricular response in digitalized patients who had atrial fibrillation or flutter, ventricular rates below 50/min at rest occurred in 15% of patients and asymptomatic hypotension occurred in 5% of patients.
The following reactions, reported in 1% or less of patients, occurred under conditions (open trials, marketing experience) where a causal relationship is uncertain; they are listed to alert the physician to a possible relationship:
Cardiovascular: angina pectoris, atrioventricular dissociation, chest pain, claudication, myocardial infarction, palpitations, purpura (vasculitis), syncope.
Digestive System: diarrhea, dry mouth, gastrointestinal distress, gingival hyperplasia.
Hemic and Lymphatic: ecchymosis or bruising.
Nervous System: cerebrovascular accident, confusion, equilibrium disorders, insomnia, muscle cramps, paresthesia, psychotic symptoms, shakiness, somnolence.
Skin: arthralgia and rash, exanthema, hair loss, hyperkeratosis, macules, sweating, urticaria, Stevens-Johnson syndrome, erythema multiforme.
Special Senses: blurred vision, tinnitus.
Urogenital: gynecomastia, galactorrhea/hyperprolactinemia, increased urination, spotty menstruation, impotence.
Treatment of Acute Cardiovascular Adverse Reactions: The frequency of cardiovascular adverse reactions that require therapy is rare; hence, experience with their treatment is limited. Whenever severe hypotension or complete AV block occurs following oral administration of verapamil, the appropriate emergency measures should be applied immediately; eg, intravenously administered norepinephrine bitartrate, atropine sulfate, isoproterenol hydrochloride (all in the usual doses), or calcium gluconate (10% solution). In patients with hypertrophic cardiomyopathy (IHSS), alpha-adrenergic agents (phenylephrine hydrochloride, metaraminol bitartrate or methoxamine hydrochloride) should be used to maintain blood pressure, and isoproterenol and norepinephrine should be avoided. If further support is necessary, dopamine hydrochloride or dobutamine hydrochloride may be administered. Actual treatment and dosage should depend on the severity of the clinical situation and the judgment and experience of the treating physician.
Overdose with verapamil may lead to pronounced hypotension, bradycardia, and conduction system abnormalities (eg, junctional rhythm with AV dissociation and high degree AV block, including asystole). Other symptoms secondary to hypoperfusion (eg, metabolic acidosis, hyperglycemia, hyperkalemia, renal dysfunction, and convulsions) may be evident.
Treat all verapamil overdoses as serious and maintain observation for at least 48 hours (especially verapamil hydrochloride extended-release tablets), preferably under continuous hospital care. Delayed pharmacodynamic consequences may occur with the extended-release formulation. Verapamil is known to decrease gastrointestinal transit time.
In overdose, tablets of verapamil hydrochloride extended-release have occasionally been reported to form concretions within the stomach or intestines. These concretions have not been visible on plain radiographs of the abdomen, and no medical means of gastrointestinal emptying is of proven efficacy in removing them. Endoscopy might reasonably be considered in cases of massive overdose when symptoms are unusually prolonged.
Treatment of overdosage should be supportive. Beta-adrenergic stimulation or parenteral administration of calcium solutions may increase calcium ion flux across the slow channel and have been used effectively in treatment of deliberate overdosage with verapamil. Continued treatment with large doses of calcium may produce a response. In a few reported cases, overdose with calcium channel blockers that was initially refractory to atropine became more responsive to this treatment when the patients received large doses (close to 1 g/hr for more than 24 hr) of calcium chloride. Verapamil cannot be removed by hemodialysis. Clinically significant hypotensive reactions or high degree AV block should be treated with vasopressor agents or cardiac pacing, respectively. Asystole should be handled by the usual measures including cardiopulmonary resuscitation.
The dose of verapamil hydrochloride extended-release tablets should be individualized by titration and the drug should be administered with food. Initiate therapy with 180 mg of extended-release verapamil hydrochloride, given in the morning. Lower initial doses of 120 mg a day may be warranted in patients who may have an increased response to verapamil (eg, the elderly or small people). Upward titration should be based on therapeutic efficacy and safety evaluated weekly and approximately 24 hours after the previous dose. The antihypertensive effects of verapamil hydrochloride extended-release tablets are evident within the first week of therapy.
If adequate response is not obtained with 180 mg of verapamil hydrochloride extended-release tablets, the dose may be titrated upward in the following manner:
a) 240 mg each morning,
b) 180 mg each morning plus
180 mg each evening; or
240 mg each morning plus
120 mg each evening,
c) 240 mg every 12 hours.
When switching from verapamil hydrochloride immediate-release tablets to verapamil hydrochloride extended-release tablets, the total daily dose in milligrams may remain the same.
Each film-coated extended-release tablet for oral administration contains 120 mg, 180 mg, or 240 mg of verapamil hydrochloride, USP.
120 mg: Yellow, oval-shaped, biconvex, film-coated tablets, debossed with “116” on one side and plain on the other side.
180 mg: Yellow, oval-shaped, biconvex, film-coated tablets, debossed with “117” on one side and scored on the other side.
240 mg: Yellow, capsule-shaped, biconvex, film-coated tablets, debossed with “118” on one side and scored on the other side.
They are supplied by State of Florida DOH Central Pharmacy as follows:
|NDC||Strength||Quantity/Form||Color||Source Prod. Code|
|53808-1019-1||180 MG||30 Tablets in a Blister Pack||YELLOW||57664-117|
Store at 20° – 25°C (68° – 77°F) [see USP Controlled Room Temperature].
Protect from light and moisture.
Dispense in a tight, light-resistant container as defined in the USP, with a child-resistant closure.
Distributed by: Caraco Pharmaceutical Laboratories, Ltd.
Detroit, MI 48202
This Product was Repackaged By:
State of Florida DOH Central Pharmacy
104-2 Hamilton Park Drive
Tallahassee, FL 32304
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