What Is Stronger: Sildenafil or Tadalafil? [Evidence-Based Comparison]

Sildenafil tends to offer slightly firmer erections and faster onset, especially at the maximum 100mg dose. Tadalafil, on the other hand, lasts much longer, up to 36 hours, and provides greater flexibility.

In clinical terms, both drugs are equally effective at their highest doses: 100mg of sildenafil ≈ and 20mg of tadalafil. The right choice depends on your lifestyle and personal preference.

How Sildenafil Works – Onset, Duration & Strengths

Sildenafil is a PDE5 inhibitor that works by increasing blood flow to the penis during sexual arousal. Its onset time typically ranges from 30 to 60 minutes, though some users may experience effects as quickly as 12 minutes. 

The peak effect is usually reached between 60 and 120 minutes after taking the dose. Sildenafil’s duration of action is generally 4 to 6 hours, although some users have reported effects lasting up to 12 hours. 

It is commonly prescribed in doses ranging from 25 mg to 100 mg as needed before sexual activity. One important consideration is that its effectiveness can be delayed if taken with a high-fat meal, so timing and diet may impact results.

Unique Strengths:

• Provides peak erection firmness in some clinical studies.
• Ideal for short-notice or occasional use.
• Generic versions are widely available and affordable.

How Tadalafil Works – Onset, Duration & Strengths

Tadalafil works through the same mechanism as sildenafil by inhibiting the PDE5 enzyme, which enhances blood flow to the penis. It stands out due to its much longer half-life, approximately 17.5 hours, giving it a significantly extended duration of action. 

Its onset time ranges from 30 to 120 minutes, although some users report feeling effects as early as 15 minutes. The peak effect typically occurs around the 2-hour mark. 

One of its biggest advantages is its long-lasting impact, with effects lasting up to 36 hours and in some cases even up to 48 hours. 

Tadalafil is available in two dosing formats: 10 to 20 mg taken as needed, or a lower daily dose of 2.5 to 5 mg for continuous readiness. Unlike sildenafil, tadalafil is not significantly affected by food intake, which makes it more flexible for use with meals.

Unique Strengths:

• Offers a longer window for spontaneous sexual activity.
• Preferred by men who want less timing pressure.
• Available as a daily dose for continuous readiness.

Head-to-Head Comparison – Strength, Effectiveness & Duration

Let’s compare sildenafil and tadalafil side by side, covering how they stack up in terms of dosage, speed, duration, and overall effectiveness.

Dosage Equivalence Chart (mg vs mg)

At maximum doses, both medications show similar success rates for achieving erections suitable for intercourse.

Onset Time – Which Acts Faster?

• Sildenafil typically works faster (30–60 mins, sometimes 12).
• Tadalafil takes slightly longer, but still within 30–120 minutes.

Duration – 4–6 Hours vs 36 Hours

• Sildenafil: Short-term effects, good for planned timing.
• Tadalafil: Extended action, perfect for multiple rounds or spontaneous plans.

Hardness & Erection Quality Studies

• Some studies show that sildenafil offers slightly firmer peak erections.
• However, tadalafil provides better psychological comfort and flexibility.

Daily Use vs On-Demand

• Sildenafil: On-demand only.
• Tadalafil: On-demand and daily dosing for ongoing effectiveness.

Side Effects & Safety Overview

Before choosing a medication, it’s important to understand the potential side effects and safety considerations.

Let’s see the common and rare side effects of both drugs to help you make an informed decision with your doctor.

Both are safe under medical supervision. Talk to your doctor about existing health conditions or other medications before use.

Real-World User Preferences & Review Insights

Surveys show 65–70% of men prefer tadalafil, mainly for its longer duration and lower pressure to time sex.

Sildenafil is preferred by those who want a shorter-acting, fast-response medication.

Both score high in satisfaction and effectiveness, so the decision often comes down to lifestyle and timing preferences.

Tadalafil or Sildenafil – Which One Should You Choose?

This section helps you decide between tadalafil and sildenafil by highlighting which lifestyle, goals, or preferences align better with each medication.

Choose Sildenafil if you:

• Prefer faster results.
• Have infrequent or planned sexual activity.
• Respond better to shorter-acting medication.
• Want a low-cost, widely available generic option.

Choose Tadalafil if you:

• Want a longer window for intimacy.
• Have frequent or spontaneous sexual activity.
• Prefer the option of daily dosing.
• Want less pressure to time things precisely.

Conclusion

There’s no single “stronger” ED medication, only what’s stronger for you. If you want peak firmness and faster onset, sildenafil may be your match. If you’re after duration, flexibility, and less timing pressure, tadalafil is likely your best bet.

Always consult with your healthcare provider to determine the right medication and dosage for your personal needs.

Sources:

ScienceDirect

NIH

Boston University Medical Campus Sexual Medicine

FAQs

1. Is 20mg of tadalafil equal to 100mg of sildenafil?

Yes, most clinical studies consider these doses roughly equivalent in effectiveness.

2. Which works faster: sildenafil or tadalafil?

Sildenafil usually kicks in faster, often within 30 minutes.

3. Which lasts longer?

Tadalafil, with effects up to 36-48 hours.

4. Which gives a harder erection?

Sildenafil may give a slightly firmer erection at its peak.

5. Can I take these medications daily?

Only tadalafil is approved for daily use.

6. Is one safer than the other?

Both are generally safe. Side effects differ slightly but are rare when used correctly.

7. Can I switch between the two?

Yes, under medical guidance.

8. Are generics available?

Yes. Generic sildenafil and tadalafil are widely available.

9. Can I take them with alcohol?

Moderate alcohol is okay, but excessive drinking can reduce effectiveness.

10. Can food affect how they work?

Sildenafil is affected by fatty meals; tadalafil is not.