What is Trospium and How Does It Work?
Trospium is a prescription medication belonging to a class of drugs known as antimuscarinics or anticholinergics. It is primarily used to treat the symptoms of overactive bladder (OAB), which include a frequent or urgent need to urinate and loss of bladder control (incontinence). The brand name for trospium, Sanctura, has been discontinued, but the medication is still widely available in its generic form.
The medication works by blocking acetylcholine, a chemical messenger, from binding to muscarinic receptors in the bladder. This action relaxes the detrusor muscle—the main muscle of the bladder wall. By reducing involuntary contractions of this muscle, trospium increases the bladder's capacity to hold urine and decreases the sensations of urgency and frequency. It is available as an immediate-release tablet and an extended-release capsule.
Administration and Considerations
Proper administration of trospium is crucial for its effectiveness and to minimize potential side effects. It must be taken on an empty stomach, at least one hour before a meal, with a glass of water. Food can significantly reduce the amount of medication absorbed by the body. The extended-release capsule should be swallowed whole and not crushed or chewed.
Dosage and administration may vary based on individual needs and medical conditions, including renal function and age. It is important to follow the specific instructions provided by a healthcare professional.
Potential Side Effects
Like all medications, trospium can cause side effects. The most common are related to its anticholinergic properties.
Common Side Effects:
- Dry mouth (the most frequent side effect, reported in up to 20% of users)
- Constipation (reported in up to 10% of users)
- Headache
- Dry eyes
- Stomach upset or pain
- Drowsiness or dizziness
Serious Side Effects: While less common, some side effects require immediate medical attention. These include:
- Angioedema: A severe allergic reaction causing swelling of the face, lips, tongue, or throat, which can be life-threatening.
- Urinary Retention: Difficulty or inability to empty the bladder.
- Central Nervous System (CNS) Effects: Confusion, hallucinations, and extreme drowsiness.
- Heat Stroke: The medication can decrease sweating, increasing the risk of overheating in hot environments.
Warnings, Interactions, and Contraindications
Before taking trospium, patients should discuss their full medical history with their healthcare provider. Trospium is contraindicated in patients with urinary retention, gastric retention (delayed stomach emptying), or uncontrolled narrow-angle glaucoma. It should be used with caution in patients with kidney disease, myasthenia gravis, ulcerative colitis, or clinically significant bladder outflow obstruction.
Drug and Other Interactions:
- Alcohol: Drinking alcohol can increase drowsiness and dizziness caused by trospium. For the extended-release capsule, alcohol should be avoided for at least two hours after taking the dose.
- Other Anticholinergic Drugs: Combining trospium with other medications that have anticholinergic effects (like certain allergy medications or antidepressants) can increase the frequency and severity of side effects like dry mouth and constipation.
- Drugs Excreted via Kidneys: Trospium may interact with other drugs that are eliminated by the kidneys, such as metformin, vancomycin, and morphine, potentially altering their concentrations in the blood.
Comparison with Other OAB Medications
Trospium is one of several anticholinergic medications used to treat overactive bladder. Others include oxybutynin and solifenacin.
| Feature | Trospium | Oxybutynin | Solifenacin |
|---|---|---|---|
| Mechanism | Non-selective antimuscarinic | Non-selective antimuscarinic | Selective M3 antimuscarinic |
| CNS Effects | Less likely to cross the blood-brain barrier, resulting in fewer CNS side effects | Associated with cognitive side effects | Can have CNS effects, though may be less than oxybutynin. |
| Common Side Effect | Dry mouth, but some studies show less dry mouth than immediate-release oxybutynin | High incidence of dry mouth | Dry mouth, constipation |
| Formulations | Immediate-release tablet, extended-release capsule | Oral liquid, tablet (IR/ER), skin patch, gel | Tablet |
Conclusion
Trospium is an effective medication for managing the symptoms of overactive bladder by relaxing the bladder muscle. Its efficacy is well-established, and its lower likelihood of causing central nervous system side effects compared to some older OAB drugs makes it a valuable option for many patients. However, its use requires careful consideration of potential side effects, drug interactions, and administration instructions, particularly the need to take it on an empty stomach. As with any prescription medication, patients should work closely with their healthcare provider to determine if trospium is the right choice for their condition.
For more detailed information, consult the official FDA label: SANCTURA (trospium chloride) 20 mg tablets
