What antidepressant causes less sweating?

Bupropion Causes Less Sweating Among Antidepressants

Bupropion is the antidepressant associated with the lowest risk of excessive sweating compared to other antidepressants, making it the preferred choice for patients concerned about hyperhidrosis as a side effect.

Understanding Antidepressant-Induced Sweating

Excessive sweating (hyperhidrosis) is a common side effect of many antidepressants, particularly affecting quality of life and potentially reducing medication adherence. According to evidence, approximately 63% of patients experience at least one adverse effect during antidepressant treatment, with sweating being among the common side effects 1.

Antidepressants Ranked by Sweating Risk

Low Risk of Sweating

• Bupropion: Has the lowest association with sweating among antidepressants
• Mirtazapine: Lower risk of serotonergic side effects including sweating 2, 3

Moderate to High Risk of Sweating

• SSRIs (Selective Serotonin Reuptake Inhibitors): Commonly cause sweating as a side effect 1
• SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors): Higher rates of sweating than SSRIs
• TCAs (Tricyclic Antidepressants): High rates of sweating and other anticholinergic side effects 4

Mechanism of Antidepressant-Induced Sweating

Sweating as a side effect is primarily related to:

• Increased serotonergic activity (particularly with SSRIs and SNRIs)
• Noradrenergic effects (more pronounced with SNRIs and TCAs)
• Anticholinergic effects (particularly with TCAs)

Evidence for Specific Antidepressants

Bupropion

• Lacks significant serotonergic activity, which is the primary mechanism behind sweating side effects
• Works primarily through dopaminergic and noradrenergic mechanisms
• Has been shown to have a lower incidence of sweating compared to SSRIs and SNRIs

Mirtazapine

• Has a unique mechanism as a noradrenergic and specific serotonergic antidepressant (NaSSA)
• Blocks 5-HT2 and 5-HT3 receptors, reducing serotonergic side effects 3
• Associated with fewer serotonergic-related adverse events than TCAs 3, 5
• "Essentially lacks serotonergic effects such as gastrointestinal symptoms, insomnia, and sexual dysfunction" 2

SSRIs

• Paroxetine, fluoxetine, sertraline, and citalopram all have similar efficacy for depression 4
• However, they commonly cause sweating as a side effect due to increased serotonergic activity

SNRIs

• Venlafaxine and desvenlafaxine have higher rates of sweating compared to SSRIs due to their dual action on serotonin and norepinephrine

TCAs

• Have high rates of anticholinergic side effects including sweating 4
• Not recommended as first-line treatment due to side effect profile 1

Clinical Considerations When Selecting Antidepressants

1. For patients concerned about sweating:

   • First choice: Bupropion
   • Second choice: Mirtazapine (though be aware of potential sedation and weight gain) 3, 6

2. For patients with comorbid conditions:

   • Sleep disturbance: Mirtazapine may be beneficial due to its sedative effects 1
   • Pain syndromes: Duloxetine may be preferred despite higher sweating risk 1
   • Anxiety with depression: SSRIs or SNRIs may be more effective but with higher sweating risk 4

3. Monitoring and management:

   • Sweating typically begins early in treatment
   • May improve over time for some patients
   • Dose reduction may help if clinically appropriate

Practical Prescribing Information

• Bupropion:

  • Starting dose: 150 mg once daily
  • Target dose: 300 mg daily (divided doses)
  • Maximum dose: 450 mg daily

• Mirtazapine:

  • Starting dose: 15 mg at bedtime
  • Target dose: 15-45 mg daily
  • Note: Lower doses (15 mg) may be more sedating than higher doses 3

Pitfalls and Caveats

1. Don't ignore other side effects when focusing solely on sweating:

   • Mirtazapine commonly causes sedation and weight gain 3, 5
   • Bupropion may cause insomnia, agitation, and has a higher seizure risk

2. Consider drug interactions:

   • Bupropion inhibits CYP2D6, potentially affecting other medications
   • Mirtazapine has minimal impact on cytochrome P450 enzymes 7

3. Remember individual variation:

   • Response to antidepressants varies significantly between individuals
   • Approximately 38% of patients do not achieve response and 54% do not achieve remission with initial treatment 1

4. Monitor for discontinuation symptoms:

   • Particularly with short-acting agents like paroxetine and venlafaxine 4
   • Taper medications gradually when discontinuing

By selecting bupropion or mirtazapine for patients concerned about sweating, clinicians can help improve medication adherence and quality of life while effectively treating depression.