Can the dose of Cialis (tadalafil) be increased?

Increasing Cialis (Tadalafil) Dosage

Yes, the dose of Cialis (tadalafil) can be increased from the starting dose to a maximum of 20mg for as-needed use or 5mg for daily use, based on individual efficacy and tolerability.

Dosing Guidelines for Erectile Dysfunction

As-Needed Dosing

• Starting dose: 10mg taken prior to anticipated sexual activity 1
• Dose adjustment:
  • Can be increased to 20mg if 10mg is insufficient
  • Can be decreased to 5mg if side effects occur
  • Maximum recommended frequency: once per day 1

Once-Daily Dosing

• Starting dose: 2.5mg taken at approximately the same time every day 1
• Can be increased to 5mg based on efficacy and tolerability 1
• Once-daily dosing may be beneficial for patients who:
  • Have frequent sexual activity (more than twice weekly)
  • Prefer continuous therapy
  • Have had incomplete response to as-needed PDE5 inhibitors 2

Special Considerations

Renal Impairment

• For as-needed use:
  • Moderate impairment (CrCl 30-50 mL/min): Maximum 10mg not more than once every 48 hours
  • Severe impairment (CrCl <30 mL/min): Maximum 5mg not more than once every 72 hours 1
• For once-daily use:
  • Moderate impairment: Start with 2.5mg, may increase to 5mg based on response
  • Severe impairment: Not recommended 1

Hepatic Impairment

• Mild to moderate impairment (Child-Pugh Class A or B):
  • As-needed use: Should not exceed 10mg once per day
  • Once-daily use: Use with caution
• Severe impairment (Child-Pugh Class C): Not recommended 1

Drug Interactions

• Potent CYP3A4 inhibitors (ketoconazole, ritonavir):
  • As-needed use: Maximum 10mg, not more than once every 72 hours
  • Once-daily use: Maximum 2.5mg 1
• Nitrates: Contraindicated due to risk of severe hypotension 3, 1
• Alpha-blockers: Patients should be stable on alpha-blocker therapy before initiating tadalafil 1

Efficacy and Safety

• Increasing from 2.5mg to 5mg daily has shown improved efficacy in clinical trials 4, 5
• In studies comparing 5mg and 10mg daily dosing, both doses significantly improved erectile function compared to placebo, with similar efficacy 4
• The percentage of patients achieving normal erectile function (IIEF-EF score ≥26) was similar between 5mg (51.5%) and 10mg (50.5%) daily dosing 4

Common Side Effects

Common adverse events include:

• Headache
• Dyspepsia (indigestion)
• Back pain
• Myalgia (muscle pain)
• Nasal congestion
• Flushing 3, 4

Important Considerations When Increasing Dose

1. Evaluate response to current dose before increasing
2. Allow sufficient trials (at least 4-8 attempts) with current dose before concluding it's ineffective
3. Ensure proper medication use (sexual stimulation is necessary, avoid large meals)
4. Consider timing of dose relative to sexual activity (effective up to 36 hours after dosing) 3, 1
5. Monitor for increased side effects with higher doses

Pitfalls to Avoid

• Avoid concurrent use with nitrates (contraindicated) 3, 1
• Don't increase dose beyond recommended maximum (20mg for as-needed, 5mg for daily)
• Don't use more frequently than recommended (once daily maximum)
• Don't combine with other PDE5 inhibitors
• Incorrect use (lack of sexual stimulation, taking with large meals) accounts for many treatment failures 3

When increasing the dose, always balance efficacy with tolerability to find the optimal dose that meets treatment expectations without unacceptable side effects.