What is the onset of action of paroxetine (selective serotonin reuptake inhibitor) for the treatment of hyperhidrosis (excessive sweating)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 30, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Paroxetine typically takes 2-8 hours to reach peak plasma concentrations, but its effectiveness for hyperhidrosis may take several weeks to notice, with some studies suggesting 2-4 weeks for noticeable improvement. When prescribing paroxetine for hyperhidrosis, it's essential to consider the dosing regimen, as the study 1 suggests that peak plasma concentrations occur 2 to 8 hours post-dose. The usual starting dose is 10-20 mg daily, which may be increased to 20-40 mg daily if needed, as seen in the treatment of premature ejaculation, where daily administration of paroxetine at 10,20, and 40 mg/day has been shown to increase ejaculatory latency 1. Some key points to consider when prescribing paroxetine for hyperhidrosis include:

  • The medication works by increasing serotonin levels in the brain, which helps regulate the body's temperature control mechanisms and sweat gland activity
  • Side effects may include dry mouth, drowsiness, sexual dysfunction, and potential withdrawal symptoms if stopped abruptly
  • It's crucial to take paroxetine consistently at the same time each day and not to discontinue without medical supervision
  • While not FDA-approved specifically for hyperhidrosis, paroxetine is prescribed off-label when other treatments like topical antiperspirants, iontophoresis, or botulinum toxin injections have failed
  • Patients should be aware that full benefits may take up to 8-12 weeks to achieve, and regular follow-up with a healthcare provider is necessary to monitor effectiveness and manage any side effects. As noted in the study 1, the optimal interval for situational dosing before intercourse has not been established, and the onset of action of these SRIs for this indication is unknown, but the study provides valuable insights into the dosing regimens and effectiveness of paroxetine in treating conditions like premature ejaculation.

From the Research

Time to Effectiveness of Paroxetine for Hyperhidrosis

  • The time it takes for paroxetine to work for hyperhidrosis is reported to be around one month, as seen in a case study where a 32-year-old man experienced a marked reduction in sweating and improvement in socio-occupational functioning after one month of treatment with paroxetine 10 mg/day, which was increased to 20 mg/day 2.
  • This improvement was sustained during follow-up at 6 months without any emergent adverse effects, suggesting that paroxetine can provide long-term relief from hyperhidrosis symptoms 2.
  • The exact mechanism of paroxetine's effect on hyperhidrosis is not fully understood, but it is thought to be related to its anticholinergic action or its antianxiety effect through central mechanisms 2.
  • While there is limited research on the specific use of paroxetine for hyperhidrosis, its efficacy and safety profile make it a potential treatment option for patients with this condition 3, 4.
  • Other treatments for hyperhidrosis, such as botulinum toxin, have also shown promise in reducing symptoms and improving quality of life for patients with this condition 5, 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Paroxetine useful for palmar-plantar hyperhidrosis.

The Annals of pharmacotherapy, 2006

Research

The pharmacological treatment and management of hyperhidrosis.

Expert opinion on pharmacotherapy, 2022

Research

Paroxetine: a review.

CNS drug reviews, 2001

Research

Botulinum toxin for hyperhidrosis: a review.

American journal of clinical dermatology, 2009

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.