Verbatim response from Perplexity
If you want the shorter-acting, usually cheaper, more “take it when needed” option, ask for sildenafil; if you want longer duration and more spontaneity, ask for tadalafil.[3][7][12] In head-to-head studies, they are similarly effective and safe overall, but tadalafil is often preferred because it lasts much longer (up to about 36 hours vs about 4–6 hours for sildenafil).[1][9][10]
For a simple rule of thumb:
- Ask for sildenafil if you want to plan sex more precisely, prefer a shorter window, or want the lower-cost option.[3][12]
- Ask for tadalafil if you want flexibility, expect sex more than once over a day or two, or want the option of a daily low-dose regimen.[3][4][7]
For a service that offers both, LloydsPharmacy Online Doctor explicitly says you can request both sildenafil and tadalafil through its service.[6] Asda Online Doctor also discusses and offers both options.[3]
If you want, I can also help you decide based on your priorities: cost, spontaneity, side effects, food interactions, or how often you have sex.