Medications for hypersalivation

What is hypersalivation? 

Antipsychotic medications such as clozapine and olanzapine, among others, may induce excessive (hyper) salivation, which can be uncomfortable and embarrassing as well as increasing the risk of aspiration pneumonia. Various pharmacological approaches have been used to try and alleviate this problem. Adjunctive medications prescribed to treat such side effects may contribute to increasing adherence to antipsychotic medications, which reduces the risk of psychotic relapse.

What is the evidence for adjunctive medications to relieve hypersalivation?

Moderate quality evidence finds the antimuscarinic propantheline can reduce hypersalivation, but it causes more constipation than placebo. The antihistamine diphenhydramine can also reduce hypersalivation, with no increases in rates of constipation when compared to placebo. The antihistamine chlorpheniramine and benzamide derivatives both reduce hypersalivation, but adverse effects were not reported.

Moderate to low quality evidence suggests traditional Chinese medicine (SuoQuan Wan) and rice bran oil derivative (oryzanolum) may be more effective than doxepin (antimuscarinic) for reducing clozapine-induced hypersalivation and may cause less constipation.

October 2020

Image: ©Melpomene – Fotolia –

Last updated at: 2:13 am, 31st August 2021
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