Hyoscyamine
An anticholinergic drug that reduces gastrointestinal and urinary tract spasms and secretions by blocking acetylcholine's action on smooth muscle.
Hyoscyamine is an anticholinergic antispasmodic used to treat GI and urinary tract spasms and related conditions.
Key facts at a glance
- ATC
- A03BA03
- RxNorm
- 153970
- Generic
- Hyoscyamine
- Class
- atc-a03
- Brands
- Hyophen, Phosphasal, Ustell, Oscimin, Donnatal, Prosed DS, Urogesic Blue Reformulated Apr 2012, Urimar Reformulated Oct 2013, Urin DS, Uro-Blue, Phenohytro, Levbid, Levsin, Uretron DS, Uribel Tabs
- Availability
- rx
- Pregnancy
- C
- Lactation
- caution
- Routes
- oral, sublingual
- Forms
- injection, tablet, solution, capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 0.25mg every 6 hours as needed
- Maximum
- consult physician
- Frequency
- every 6 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 0.125mg every 4-6 hours as needed
- Maximum
- consult physician
- Frequency
- every 4-6 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 0.125mg every 6-8 hours as needed
- Maximum
- consult physician
- Frequency
- every 6-8 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks
regular fetal monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
second trimesteruse lowest effective dose
use only if clearly needed and benefits outweigh risks
fetal growth monitoring
Use with caution and monitor for adverse effects.
pregnancy
third trimesteravoid if possible
avoid near term due to potential uterine relaxation
fetal monitoring and uterine activity
Use of this medication in this population requires careful consideration of risks and benefits.
lactation
breastfeedinguse lowest effective dose
discontinue breastfeeding or avoid drug; may cause infant sedation
monitor infant for excessive drowsiness
Use with caution and monitor for adverse effects.
geriatric
elderlyreduce dose by 50%
start with low dose; monitor for confusion and falls
cognitive function and fall risk assessment
Use with caution and monitor for adverse effects.
pediatric_age
childrennot recommended for children under 12 years
avoid in children due to anticholinergic toxicity risk
not applicable for this population
Use of this medication in this population requires careful consideration of risks and benefits.
renal_impairment
severereduce dose by 50%
use with caution; monitor renal function
renal function monitoring
Use with caution and monitor for adverse effects.
hepatic_impairment
severereduce dose by 50%
use with caution; monitor liver function
liver function monitoring
Use with caution and monitor for adverse effects.
Statistics and clinical data
Drug class
Muscarinic antagonist medication classification
Mechanism of action
Blocks acetylcholine receptors to reduce smooth muscle spasms
Common uses
Therapeutic indications for Hyoscyamine
Commonly prescribed since
Long-standing availability as prescription medication
Hyoscyamine is used to treat irritable bowel syndrome, peptic ulcers, spastic colitis, bladder spasms, urinary frequency, cystitis, and bradycardia. It may also be used as an antisecretory agent and for symptoms associated with Parkinson's disease.
Hyoscyamine is an alkaloid derived from plants such as henbane and jimsonweed. It works by competitively blocking muscarinic acetylcholine receptors, which reduces smooth muscle contractions in the GI and urinary tracts and decreases associated secretions.
Common side effects include dry mouth, blurred vision, constipation, and urinary retention. Caution is advised in patients with glaucoma, benign prostatic hyperplasia, or cardiovascular disease. Should be used with particular care in elderly patients due to increased sensitivity to anticholinergic effects.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 24, 2026. · Read our editorial policy