Drug interactions
Hyoscyamine + Meclizine
Severity: Moderate
Hyoscyamine and Meclizine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Both drugs block muscarinic receptors, so combined use can cause additive dry mouth, constipation, urinary retention, blurred vision, tachycardia and confusion. Older adults are at highest risk.
What this interaction means in plain words
Hyoscyamine and Meclizine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Hyoscyamine belongs to Genitourinary; Meclizine belongs to Respiratory.
Why it happens
Additive antimuscarinic effects.
What to do
Monitor for anticholinergic toxicity and reduce doses or choose a non-anticholinergic alternative if symptoms occur. Avoid in narrow-angle glaucoma and urinary obstruction.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Meclizine
Other interactions of Hyoscyamine
- Amantadine + Hyoscyamine Moderate
- Amitriptyline + Hyoscyamine Moderate
- Aripiprazole + Hyoscyamine Moderate
- Atropine + Hyoscyamine Moderate
- Benztropine + Hyoscyamine Moderate
- Bethanechol + Hyoscyamine Moderate
Frequently asked questions
Can I take Hyoscyamine with Meclizine?
MediHelp rates the interaction as moderate. Hyoscyamine and Meclizine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Both drugs block muscarinic receptors, so combined use can cause additive dry mouth, constipation, urinary retention, blurred vision, tachycardia and confusion. Older adults are at highest risk.
How serious is the interaction between Hyoscyamine and Meclizine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for anticholinergic toxicity and reduce doses or choose a non-anticholinergic alternative if symptoms occur. Avoid in narrow-angle glaucoma and urinary obstruction.
What other medicines interact with Meclizine?
MediHelp also lists interactions of Meclizine with, for example, Belladonna and opium, Benzhydrocodone / acetaminophen, Brexanolone. The full list is on the Meclizine page.
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