When should I take tadalafil (phosphodiesterase type 5 inhibitor) for erectile dysfunction?

When to Take Tadalafil for Erectile Dysfunction

Tadalafil can be taken either as needed at least 30 minutes before anticipated sexual activity or once daily at approximately the same time every day, depending on the dosing regimen chosen. 1

As-Needed Dosing

• The recommended starting dose for as-needed use is 10 mg taken prior to anticipated sexual activity, which may be increased to 20 mg or decreased to 5 mg based on individual efficacy and tolerability 1
• Tadalafil should be taken at least 30 minutes before sexual activity, as significant erectogenic effects begin within this timeframe 2
• The medication remains effective for up to 36 hours after dosing, providing a longer window for sexual activity compared to other PDE5 inhibitors 3, 1
• The maximum recommended dosing frequency is once per day for most patients 1
• Tadalafil can be taken with or without food, as food does not significantly affect its absorption 1

Once-Daily Dosing

• The recommended starting dose for once-daily use is 2.5 mg, taken at approximately the same time every day, without regard to timing of sexual activity 1
• The dose may be increased to 5 mg based on individual efficacy and tolerability 1
• Daily dosing provides an alternative for couples who prefer spontaneous rather than scheduled sexual activity 4
• Once-daily dosing eliminates the need to temporally link medication intake with sexual activity 5

Special Considerations

• Sexual stimulation is necessary for the medication to be effective, as PDE5 inhibitors do not work without sexual arousal 3
• Patients should be advised that substantial alcohol consumption in combination with tadalafil can increase the potential for orthostatic symptoms (increased heart rate, decreased blood pressure, dizziness, headache) 1
• Tadalafil is absolutely contraindicated with nitrate medications due to the risk of severe hypotension 6, 3
• For patients who have taken tadalafil, nitrates should be avoided for at least 48 hours in case of a medical emergency 4

Dosing in Special Populations

• For patients with renal impairment (creatinine clearance 30-50 mL/min): For as-needed use, start with 5 mg with maximum dose of 10 mg not more than once every 48 hours 1
• For severe renal impairment (creatinine clearance <30 mL/min): Maximum dose is 5 mg not more than once every 72 hours for as-needed use; once-daily use is not recommended 1
• For patients with mild to moderate hepatic impairment: Dose should not exceed 10 mg once per day 1
• For severe hepatic impairment: Tadalafil use is not recommended 1

Efficacy and Timing

• Studies show that 52% of men taking tadalafil 20 mg had at least one successful intercourse attempt within 30 minutes compared to 35.1% of men taking placebo 2
• Most patients attempt sexual intercourse at least once at 12-36 hours after taking tadalafil, taking advantage of its extended duration of action 7
• Regardless of age, ED severity, or previous experience with other PDE5 inhibitors, patients using tadalafil typically attempt intercourse across various time intervals after dosing 7

Safety Considerations

• Patients should be advised to seek emergency medical attention for erections lasting longer than 4 hours 1
• Before initiating treatment, cardiovascular risk should be assessed, with high-risk patients requiring cardiologist evaluation before starting therapy 4