Verbatim response from Perplexity
If you want the most flexibility and spontaneity, ask for tadalafil; if you want something for planned, on-demand use, ask for sildenafil.[2][4][5] In head-to-head reviews, they are broadly similarly effective for erectile dysfunction, but tadalafil lasts much longer and is often preferred for its longer “coverage window.”[1][4][8]
Which to ask for depends on your priorities:
- Tadalafil: lasts up to 36 hours, can be taken as needed or daily in low-dose form, and is usually better if you want less timing pressure.[2][4][5][8]
- Sildenafil: works for about 4–6 hours and is usually best if you prefer a more short-acting, planned option.[2][4][5][7]
- If you’re trying one for the first time, some clinicians suggest trying both separately to see which gives the best effect with the fewest side effects.[7]
For side effects, the tradeoff is typical: tadalafil is associated more with back pain/myalgia, while sildenafil is more associated with flushing and sometimes visual changes.[1][6]
As for services that offer both, these explicitly say they provide both sildenafil and tadalafil:
- LloydsPharmacy Online Doctor: states you can request both safely online.[2]
- Asda Online Doctor: offers both and compares them directly.[5]
If you want, I can also help you decide which one fits your situation based on whether you want occasional use, daily use, or you have side-effect concerns.