Cialis vs. Viagra
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Cialis (tadalafil) and Viagra (sildenafil) are the two most prescribed ED medications worldwide. They work through the same mechanism but have different durations, onset times, and pharmacokinetic profiles.
The key difference is duration: sildenafil lasts 4–6 hours while tadalafil lasts up to 36 hours. Neither works better overall — preference is individual.
Side-by-Side Comparison
| Feature | Cialis (Tadalafil) | Viagra (Sildenafil) |
|---|---|---|
| Duration | Up to 36 hours (as-needed) | 4–6 hours |
| Onset | 30–60 minutes | 30–60 minutes |
| Food interaction | Minimal | High-fat meals delay absorption |
| Generic available? | Yes (tadalafil) | Yes (sildenafil) |
Who Each Option May Fit
Who May Prefer Tadalafil (Cialis)
Men who prefer spontaneity and flexibility — not needing to time a pill closely to activity. Tadalafil's 36-hour window removes much of the pressure to plan ahead.
Who May Prefer Sildenafil (Viagra)
Men who prefer a shorter, more defined window of effect, or those who take medications that interact more with tadalafil.
Common Questions
Can I take both Cialis and Viagra?
No — these should not be combined. Taking two PDE5 inhibitors simultaneously significantly increases the risk of dangerous blood pressure drops.
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