VisRx Dose Pack Dosage
Generic name: pseudoephedrine, methscopolamine, and chlorpheniramine
Dosage form: controlled-release tablets
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VisRx should be used with caution in patients with diabetes mellitus, hypertension, cardiovascular disease, and hyperactivity to sympathomimetic amines. Antihistamines may cause drowsiness, and ambulatory patients who operate machinery or motor vehicles should be cautioned accordingly. Methscopolamine nitrate should be used with caution in the elderly and all patients with autonomic neuropathy, hepatic or renal disease, or ulcerative colitis.
Do not prescribe VisRx for use in patients that are now taking prescription MAOIs (certain drugs for depression, psychiatric or emotional conditions, or Parkinson’s disease), or for 14 days after stopping MAOI drug therapy. Beta-adrenergic blockers and MAOIs may potentiate the pressor effect of pseudoephedrine HCl. Concurrent use of digitalis glycosides may increase the possibility of cardiac arrhythmias. Sympathomimetics may reduce the hypotensive effects of guanethidine, mecamylamine, methyldopa, reserpine and veratrum alkaloids. Concurrent use of pseudoephedrine HCl with other sympathomimetic amines may increase pressor or cardiovascular effects of either medication.
The use of pseudoephedrine HCl may result in additive CNS depressant effects when coadministered with alcohol, antihistamines, psychotropics, or other drugs which produce CNS depression. Concurrent use of tricyclic antidepressants may antagonize the effects of pseudoephedrine HCl.
Additive anticholinergic effects may result from concomitant use with antipsychotics, tricyclic antidepressants, and other drugs with anticholinergic effects. Concomitant administration with antacids may interfere with the absorption of methscopolamine nitrate.
Carcinogenesis,Mutagenesis, Impairment of Fertility
Animal studies to assess the long-term carcinogenic and mutagenic potential or the effect on fertility in animals or humans have not been performed.
Pregnancy: Category C
It is not known whether VisRx can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. VisRx should be given to a pregnant woman only if clearly needed.
It is not known whether this combination drug is excreted in human milk. However, pseudoephedrine HCl administered alone distributes into the breast milk of lactating human females; therefore, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
The safety and effectiveness in children under 12 years of age have not been established.
The elderly (60 years and older) are more likely to experience adverse reactions to sympathomimetics. Overdosage of sympathomimetics in this age group may cause hallucinations, convulsions, CNS depression, and/or death. Pseudoephedrine HCl is known to be substantially excreted by the kidneys 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, care should be taken in dose selection, and it may be useful to monitor renal function.
Adverse reactions include drowsiness, lassitude, nausea, giddiness, dryness of mouth, blurred vision, cardiac palpitations, flushing, and increased irritability or excitement (especially in children). Some individuals may display sympathomimetic amine effects such as tachycardia, palpitations, headache, dizziness, or nausea. Sympathomimetics have been associated with certain untoward reactions including fear, anxiety, nervousness, restlessness, tremor, weakness, pallor, respiratory difficulty, dysuria, insomnia, hallucinations, convulsions, CNS depression, arrhythmias, and cardiovascular collapse with hypotension. Urinary retention may occur in patients with prostatic hypertrophy. Antihistamines and anticholinergics may cause drowsiness, dizziness, blurred vision, and excessive dryness of the nose, throat, and mouth.
DRUG ABUSE AND DEPENDENCE
Rebound congestion may occur after vasoconstriction subsides when pseudoephedrine HCl is discontinued. Patients may increase the amount of drug and frequency of use, producing toxicity and perpetuating the rebound congestion. Excessive use may cause systemic effects which are more likely in the elderly. Habituation and toxic psychosis have followed long-term, high-dose therapy.
OVERDOSAGE AND TREATMENT OF OVERDOSAGE
The treatment of overdosage should provide symptomatic and supportive care. Induction of emesis and gastric lavage may be performed if the patient is alert and seen within early hours after ingestion. Drug remaining in the stomach may be absorbed by the administration of activated charcoal. Stimulants should not be used because they may precipitate convulsions. If convulsions or marked CNS excitement occurs, treatment with appropriate measures is indicated. Since the effects of VisRx last up to 12 hours, the patient should be monitored for at least that length of time and treated as necessary.