Starting Dose of Cialis (Tadalafil) for Erectile Dysfunction
The recommended starting dose of Cialis (tadalafil) for erectile dysfunction when used as needed is 10 mg taken prior to anticipated sexual activity. 1
Dosing Guidelines
Tadalafil offers two distinct dosing regimens for treating erectile dysfunction:
As-Needed Dosing
- Starting dose: 10 mg taken prior to anticipated sexual activity
- Dose adjustment: May be increased to 20 mg or decreased to 5 mg based on individual efficacy and tolerability
- Maximum frequency: Once per day in most patients
- Timing: Can be taken without regard to food
- Duration of effect: Improves erectile function for up to 36 hours following dosing 1, 2
Once-Daily Dosing
- Starting dose: 2.5 mg taken at approximately the same time every day
- Dose adjustment: May be increased to 5 mg based on individual efficacy and tolerability
- Timing: Taken without regard to timing of sexual activity 1
Special Population Considerations
Renal Impairment (As-Needed Dosing)
- Moderate impairment (CrCl 30-50 mL/min): Starting dose of 5 mg not more than once per day; maximum 10 mg not more than once every 48 hours
- Severe impairment (CrCl <30 mL/min or on hemodialysis): Maximum 5 mg not more than once every 72 hours 1
Hepatic Impairment
- Mild to moderate (Child-Pugh Class A or B): Dose should not exceed 10 mg once per day
- Severe (Child-Pugh Class C): Use not recommended 1
Efficacy and Safety
Tadalafil has demonstrated significant efficacy in treating erectile dysfunction:
- Clinical trials show that both as-needed and once-daily dosing significantly improve erectile function compared to placebo 3, 4
- Once-daily tadalafil 5 mg has shown long-term safety and efficacy in studies up to 2 years 4
- The 36-hour window of effectiveness allows greater spontaneity in sexual activity compared to shorter-acting PDE5 inhibitors 2
Common Side Effects
The most frequently reported adverse events with tadalafil include:
Most side effects are mild to moderate in severity and transient in nature.
Important Considerations
- Tadalafil should not be used in patients taking nitrates due to risk of potentially dangerous hypotension 6
- Tadalafil tablets should not be split; the entire dose should be taken 1
- For patients transitioning from other treatments for erectile dysfunction, tadalafil offers the advantage of a longer window of effectiveness 2
- Long-term studies show tadalafil maintains its efficacy and safety profile over extended periods of use 4, 5