Verbatim response from Perplexity
You should ask for tadalafil if you want flexibility and spontaneity (lasting up to 36 hours), or sildenafil if you prefer a shorter window of effect (4–6 hours) and potentially lower cost; both are similarly effective, but tadalafil is generally preferred by patients and partners due to its longer duration and lack of food interaction [1][2][5].
Key Differences to Help You Decide
| Feature | Sildenafil (Viagra) | Tadalafil (Cialis) |
|---|---|---|
| Duration | 4–6 hours | Up to 36 hours ("weekend pill") [1][5] |
| Onset | 30–60 mins | 30–60 mins (peak at 2 hrs) [1][5] |
| Food Interaction | Less effective with fatty meals | No significant food interaction [3][5] |
| Dosing Options | On-demand only | On-demand or daily (low dose) [3][5] |
| Patient Preference | Slightly more penetrative success in some studies | Preferred by most men/partners [1][2] |
- Choose tadalafil if: You want spontaneity, have frequent sexual activity, manage BPH (benign prostatic hyperplasia), or prefer not to plan around a short time window [3][5][11].
- Choose sildenafil if: You prefer occasional use, want the lowest pharmacy cost, or prefer a shorter duration in your system [1][11].
Services Offering Both
You can request both sildenafil and tadalafil safely online through these services:
- LloydsPharmacy Online Doctor: Explicitly offers both and notes men often prefer tadalafil for its speed and duration [6].
- ASDA Online Doctor: Provides a comparison and telehealth service for both [5].
- Numan: Offers a consultation to determine which fits your lifestyle [7].
- Ro (ro.co): Provides ED treatment including both options [8].
Most urologists recommend trying both separately first to see which works best for you with the fewest side effects, as prices for generics are now low enough to safely test both [1].