Are sedatives such as quetiapine (Seroquel), gabapentin (Neurontin), or clonazepam (Klonopin) contributing to my erectile dysfunction (ED), and which ones can be reduced or replaced to minimize this side effect?

Management of Medication-Induced Erectile Dysfunction

Quetiapine, gabapentin, and clonazepam are all likely contributing to your erectile dysfunction, with quetiapine and clonazepam being the most significant contributors that should be reduced first while maintaining mirtazapine at 7.5mg.

Medication Effects on Sexual Function

Primary Culprits

• Benzodiazepines (Clonazepam): Strong evidence links benzodiazepines to sexual dysfunction through enhanced GABA-A receptor function which reduces penile erection 1
• Antipsychotics (Quetiapine): Associated with significant sexual side effects including erectile dysfunction 2
• Gabapentinoids (Gabapentin): Can cause sexual dysfunction even at low doses (300mg daily) 3, 4

Current Regimen Analysis

Your current medication regimen includes multiple sedating agents that overlap in their mechanisms and side effects:

• Quetiapine 50mg (antipsychotic)
• Gabapentin 200mg (anticonvulsant)
• Clonazepam 0.625mg (benzodiazepine)
• Mirtazapine 7.5mg (tetracyclic antidepressant)
• Tadalafil 5mg (PDE-5 inhibitor)
• Modafinil 100mg (wakefulness-promoting agent)

Recommended Medication Adjustments

Step 1: Reduce Sedative Burden

1. First medication to reduce: Quetiapine

   • Gradually taper down from 50mg to 25mg over 1-2 weeks
   • Monitor for return of nocturnal erections
   • If no improvement after 2 weeks at 25mg, consider further reduction

2. Second medication to reduce: Clonazepam

   • After quetiapine reduction, begin tapering clonazepam by 0.125mg every 1-2 weeks
   • Never stop benzodiazepines abruptly due to withdrawal risk

3. Maintain: Mirtazapine 7.5mg

   • Keep this medication stable as it's generally better tolerated for sexual function at lower doses 5

4. Consider later: Gabapentin reduction

   • If erectile dysfunction persists after reducing the above medications, consider tapering gabapentin

Step 2: Optimize Current ED Treatment

• Continue Tadalafil 5mg daily (optimal for continuous coverage) 5
• Ensure you're taking it consistently for maximum effect

Monitoring and Follow-up

• Assess for return of nocturnal erections within 2 weeks of each medication adjustment
• Monitor for withdrawal symptoms from sedative tapering
• Evaluate sexual function improvement using validated questionnaires
• Reassess hormonal status after 6 weeks if no improvement

Alternative Medication Options

If sexual dysfunction persists after medication adjustments:

Alternative Sedatives with Lower Sexual Side Effect Profiles

• For anxiety/sleep: Consider buspirone (20-60mg/day) which has minimal impact on sexual function 5
• For mood: Bupropion (starting 37.5mg, target 150mg twice daily) has lower rates of sexual side effects 5

Combination Approaches

• Combination of bupropion with tadalafil may provide synergistic benefits for both mood and sexual function 5

Important Cautions

• Never discontinue benzodiazepines or antipsychotics abruptly
• Tapering schedules must be individualized based on response
• Monitor for emergence of underlying psychiatric symptoms during medication changes
• Some degree of sedation may be necessary for your condition; balance this with sexual function goals

By systematically reducing your sedative burden starting with quetiapine and then clonazepam while maintaining mirtazapine, you have the best chance of improving erectile function while maintaining symptom control.