Symax FasTab Side Effects
Generic Name: hyoscyamine
Note: This page contains side effects data for the generic drug hyoscyamine. It is possible that some of the dosage forms included below may not apply to the brand name Symax FasTab.
For the Consumer
Applies to hyoscyamine: oral conventional tablets and sublingual tablets, oral extended-release capsules and tablets, oral oral solution and elixir, oral orally disintegrating tablets, parenteral injection
Side effects include:
Most adverse effects are manifestations of pharmacologic effects at muscarinic-cholinergic receptors and usually are reversible when therapy is discontinued.
Severity and frequency of adverse effects are dose related and individual intolerance varies greatly; adverse effects occasionally may be obviated by a reduction in dosage but this also may eliminate potential therapeutic effects.
Adverse effects include dry mouth, urinary hesitancy and retention, blurred vision, tachycardia, palpitations, mydriasis, increased ocular tension, loss of taste, headache, nervousness, drowsiness, weakness, fatigue, dizziness, insomnia, nausea, vomiting, impotence, constipation, bloated feeling, abdominal pain, diarrhea, allergic reactions or drug idiosyncrasies, urticaria and other dermal manifestations, ataxia, speech disturbance, mental confusion and/or excitement (especially in geriatric patients), short-term memory loss, hallucinations, and decreased sweating.
For Healthcare Professionals
Applies to hyoscyamine: compounding powder, injectable solution, oral capsule extended release, oral liquid, oral solution, oral spray, oral tablet, oral tablet chewable, oral tablet disintegrating, oral tablet extended release, sublingual tablet
Cardiovascular side effects have included tachycardia, premature ventricular depolarizations, and ventricular tachycardia.[Ref]
Gastrointestinal side effects due to the anticholinergic effects of hyoscyamine (the active ingredient contained in Symax FasTab) have commonly included dry mouth and mucous membranes. Other reported side effects include delayed gastric emptying time, reduced gastric acid secretion, constipation, and gastroesophageal reflux.[Ref]
Hyoscyamine (the active ingredient contained in Symax FasTab) toxicity (anticholinergic side effects) often presents as fever, tachycardia, agitation, and dry skin/mucous membranes.[Ref]
Genitourinary complications include urinary retention (due to anticholinergic effects on the urinary sphincter), which is common and dose-related, and impotence in male patients.[Ref]
Hypersensitivity reactions to hyoscyamine (the active ingredient contained in Symax FasTab) are rare. Reactions can include urticaria, eczema, papillary hyperplasia, mucopurulent discharge, eosinophilia, pruritus, edema, hypotension, abdominal pain, tachypnea, nausea and vomiting.[Ref]
Nervous system side effects have included lethargy and somnolence. Higher doses may be associated with mental confusion and/or excitement. The elderly appear to be more prone to the anticholinergic effects of hyoscyamine (the active ingredient contained in Symax FasTab) on the CNS.[Ref]
Ocular side effects due to the anticholinergic activity of hyoscyamine (the active ingredient contained in Symax FasTab) have included inhibition of the iris sphincter muscle (possibly resulting in mydriasis), follicular conjunctivitis, and inhibition of the ciliary muscle (which can produce blurred vision). All muscarinic antagonists can precipitate glaucoma.[Ref]
Endocrine side effects have included inhibition of exocrine sweat glands. This is usually not clinically significant except when perspiration becomes a major factor in body temperature control.[Ref]
1. "Product Information. Levsin (L-hyoscyamine)." Schwarz Pharma, Mequon, WI.
It is possible that some side effects of Symax FasTab may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.
More about Symax FasTab (hyoscyamine)
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