What is the proper use and dosage of Cialis (tadalafil) 5 mg tablets for erectile dysfunction or benign prostatic hyperplasia?

Tadalafil 5 mg for Erectile Dysfunction and Benign Prostatic Hyperplasia

For erectile dysfunction, tadalafil 5 mg once daily is an effective treatment option that can be taken at approximately the same time every day without regard to timing of sexual activity. 1 For benign prostatic hyperplasia (BPH), tadalafil 5 mg once daily is recommended to be taken at approximately the same time every day. 1

Dosing and Administration

For Erectile Dysfunction:

• Starting dose options:
  • Once daily use: 2.5 mg taken at approximately the same time every day, may be increased to 5 mg based on efficacy and tolerability 1
  • As needed use: 10 mg taken prior to anticipated sexual activity, may be increased to 20 mg or decreased to 5 mg based on individual response 1

For BPH:

• Standard dose: 5 mg once daily, taken at approximately the same time every day 1
• When initiating therapy for BPH with tadalafil and finasteride, the recommended dose is 5 mg once daily for up to 26 weeks 1

For Combined ED and BPH:

• Recommended dose: 5 mg once daily, taken at approximately the same time every day 1

Efficacy

• For ED: Tadalafil 5 mg once daily significantly improves erectile function compared to placebo, with improvements in International Index of Erectile Function (IIEF) scores 2
• For BPH: Tadalafil 5 mg once daily significantly improves International Prostate Symptom Score (IPSS) compared to placebo 3, 4
• For combined ED/BPH: Tadalafil 5 mg improves both IIEF-EF domain scores and IPSS scores in men with both conditions 5

Administration Considerations

• May be taken without regard to food 1
• Do not split tablets; entire dose should be taken 1
• Tadalafil can improve erectile function for up to 36 hours following dosing 1
• Sexual stimulation is necessary for tadalafil to work effectively 6

Dose Adjustments

Renal Impairment:

• Creatinine clearance 30-50 mL/min:
  • For once daily use: Start with 2.5 mg, may increase to 5 mg based on response 1
  • For as-needed use: Start with 5 mg, maximum 10 mg not more than once every 48 hours 1
• Creatinine clearance <30 mL/min or on hemodialysis:
  • Once daily use is not recommended 1
  • For as-needed use: Maximum 5 mg not more than once every 72 hours 1

Hepatic Impairment:

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

Drug Interactions

• Nitrates: Concomitant use is absolutely contraindicated due to risk of severe hypotension 6, 1
• Alpha-blockers:
  • For ED: Patients should be stable on alpha-blocker therapy before starting tadalafil, which should be initiated at the lowest recommended dose 1
  • For BPH: Tadalafil is not recommended in combination with alpha-blockers 1
• CYP3A4 inhibitors (e.g., ketoconazole, ritonavir):
  • For once daily use: Maximum recommended dose is 2.5 mg 1
  • For as-needed use: Maximum 10 mg, not to exceed once every 72 hours 1

Common Side Effects

The most frequently reported adverse events with PDE5 inhibitors are:

• Dyspepsia
• Headache
• Flushing
• Back pain
• Nasal congestion
• Myalgia
• Visual disturbance
• Dizziness 3

Special Considerations

• Men with diabetes or post-prostatectomy may have more severe ED at baseline and respond less robustly to PDE5 inhibitors 3, 6
• For patients with both ED and BPH, tadalafil 5 mg once daily is an effective treatment option addressing both conditions 3, 5
• When prescribing for BPH, tadalafil should be discussed as a treatment option irrespective of comorbid ED 3
• Tadalafil should not be used in combination with alpha-blockers for BPH treatment 3

Monitoring and Follow-up

• Assess treatment response and side effects
• For patients with both ED and BPH, monitor improvements in both IPSS and erectile function
• Ensure proper medication use to maximize efficacy

By following these guidelines, tadalafil 5 mg can be effectively and safely used for the treatment of erectile dysfunction, benign prostatic hyperplasia, or both conditions concurrently.