From the Research
Nefopam hydrochloride should be used with caution in patients with gastroparesis, though it is not absolutely contraindicated. Patients with gastroparesis may experience worsened symptoms when taking nefopam due to its anticholinergic properties, which can further delay gastric emptying and exacerbate nausea, vomiting, and abdominal discomfort. If nefopam is prescribed to a patient with gastroparesis, it should be started at a lower dose (such as 30mg three times daily instead of the usual 60mg three times daily) and the patient should be monitored closely for worsening gastroparesis symptoms.
Key Considerations
- Alternative analgesics without significant anticholinergic effects might be preferable for these patients.
- The mechanism behind this caution is that nefopam inhibits the reuptake of serotonin, norepinephrine, and dopamine, and has moderate anticholinergic effects that can reduce gastrointestinal motility.
- For patients with gastroparesis who require nefopam for pain management, combining it with a prokinetic agent might help mitigate the negative effects on gastric emptying, though this approach requires careful monitoring 1.
Potential Side Effects
- Nefopam has been associated with various side effects, including sweating, nausea, tachycardia, malaise, and vomiting 2.
- In rare cases, nefopam can cause serious adverse reactions, such as convulsions and anaphylactic shocks, especially in patients with special medical conditions, like post-operative periods 2.
Pharmacokinetics and Metabolism
- Nefopam is extensively metabolized in the liver, with multiple metabolites identified in plasma, urine, and feces 3.
- The pharmacokinetics of nefopam may be affected by various factors, including age, renal function, and concomitant medication use.