Improvement of dry mouth by replacing paroxetine with fluvoxamine

Yuka Arima, Chiharu Kubo, Masayuki Tsujimoto, Hisakazu Ohtani, Yasufumi Sawada

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


OBJECTIVE: To present a case of improvement of paroxetine-induced dry mouth by substitution of fluvoxamine and analyze this case based on receptor occupancy theory. CASE SUMMARY: A 66-year-old woman with major depressive disorder had been treated with brotizolam 0.5 mg/day, flunitrazepam 2 mg/day, sulpiride 100 mg/day, bromazepam 2 mg/day, trazodone 25 mg/day, and paroxetine hydrochloride 10 mg/day. Although her psychological symptoms improved gradually, she complained of dry mouth. Paroxetine was replaced with fluvoxamine maleate 50 mg/day, and the dryness disappeared within a month. DISCUSSION: We calculated the time courses of muscarinic acetylcholine (mACh) receptor occupancy after oral administration of paroxetine and fluvoxamine at the treatment doses by using pharmacokinetic parameters obtained from the literature. The mACh receptor occupancy was estimated to be decreased from 0.22% to 0.020% by replacing paroxetine with fluvoxamine. CONCLUSIONS: The improvement of dry mouth observed after the replacement of paroxetine with fluvoxamine in this patient may have been due to a decrease in the mACh receptor occupancy.

Original languageEnglish
Pages (from-to)567-571
Number of pages5
JournalAnnals of Pharmacotherapy
Issue number3
Publication statusPublished - Mar 2005
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Pharmacology (medical)


Dive into the research topics of 'Improvement of dry mouth by replacing paroxetine with fluvoxamine'. Together they form a unique fingerprint.

Cite this