What is the highest daily dose of tadalafil (Cialis) for erectile dysfunction (ED) and benign prostatic hyperplasia (BPH)?

Maximum Daily Dose of Tadalafil

The maximum daily dose of tadalafil is 20 mg for erectile dysfunction (ED) when used as needed, and 5 mg for once-daily use in both ED and benign prostatic hyperplasia (BPH). 1

Dosing Guidelines for Erectile Dysfunction

As-Needed Dosing

• The recommended starting dose is 10 mg taken prior to anticipated sexual activity 1
• The dose may be increased to 20 mg or decreased to 5 mg based on individual efficacy and tolerability 1
• Maximum recommended dosing frequency is once per day 1
• Tadalafil can improve erectile function for up to 36 hours following dosing 1
• Higher doses (50 mg vs 25 mg) of sildenafil show improved erectile function, but this dose-response relationship was not observed with tadalafil (20 mg vs 10 mg vs 5 mg) 2

Once-Daily Dosing for ED

• The recommended starting dose is 2.5 mg taken at approximately the same time every day 1
• The dose may be increased to 5 mg based on individual efficacy and tolerability 1
• Once-daily dosing provides an alternative for couples who prefer spontaneous rather than scheduled sexual activity 2
• Clinical trials have demonstrated that once-daily tadalafil (5 mg and 10 mg) is well tolerated and significantly improves erectile function in men with ED 3

Dosing for Benign Prostatic Hyperplasia (BPH)

• The recommended dose for BPH treatment is 5 mg once daily 1, 2
• When tadalafil is initiated with finasteride for BPH treatment, the recommended dose remains 5 mg once daily for up to 26 weeks 1
• For patients with both ED and BPH, the recommended dose is also 5 mg once daily 1
• Tadalafil 5 mg daily should be discussed as a treatment option for patients with LUTS/BPH regardless of comorbid erectile dysfunction 2

Special Population Considerations

Renal Impairment

• For as-needed use in patients with creatinine clearance 30-50 mL/min: maximum 10 mg not more than once every 48 hours 1
• For as-needed use in patients with creatinine clearance <30 mL/min: maximum 5 mg not more than once every 72 hours 1
• For once-daily use in ED: not recommended if creatinine clearance <30 mL/min 1
• For once-daily use in BPH or ED/BPH with creatinine clearance 30-50 mL/min: start with 2.5 mg, may increase to 5 mg based on response 1
• For once-daily use in BPH or ED/BPH with creatinine clearance <30 mL/min: not recommended 1

Hepatic Impairment

• For as-needed use in mild to moderate impairment (Child-Pugh Class A or B): maximum 10 mg once per day 1
• For severe hepatic impairment (Child-Pugh Class C): tadalafil use is not recommended 1
• For once-daily use in any hepatic impairment: caution is advised, and use is not recommended in severe impairment 1

Combination Therapy Considerations

• Clinicians should not offer the combination of low-dose daily 5 mg tadalafil with alpha blockers for LUTS/BPH as it offers no advantages in symptom improvement over either agent alone 2
• However, some research suggests tadalafil 5 mg once daily in combination with alpha blockers may have few adverse effects on hypotensive events and can improve LUTS and restore sexual function 4
• Concomitant use of nitrates in any form is contraindicated due to risk of severe hypotension 1

Common Side Effects

• Most common adverse effects include headache, flushing, rhinitis, and dyspepsia 2
• Less common adverse effects include visual disturbances, myalgia, nausea, diarrhea, vomiting, dizziness, and chest pain 2
• The incidence of serious adverse events is less than 2%, with no significant difference between PDE5 inhibitors and placebo 2

Clinical Efficacy

• Tadalafil significantly improves erectile function compared to placebo, with approximately 69% of men reporting improved erections versus 33% with placebo 2
• For BPH treatment, tadalafil 5 mg daily improves International Prostate Symptom Score (IPSS) compared to placebo 2, 5
• Tadalafil can also improve ejaculatory function and sexual satisfaction in men with LUTS/BPH and ED 6

Remember that while the maximum dose for as-needed use is 20 mg daily, the maximum dose for once-daily use is 5 mg, regardless of whether it's used for ED, BPH, or both conditions.