Can I increase my sildenafil (20 mg) dose from three tablets as needed to a higher dose if it is not effective?

Can You Increase Your Sildenafil Dose Beyond 60 mg (Three 20 mg Tablets)?

No, you should not exceed 60 mg total daily dose when taking sildenafil 20 mg tablets for pulmonary arterial hypertension (PAH), as this is the maximum FDA-approved dose for this indication. However, if you're taking sildenafil for erectile dysfunction (ED), the situation is different—the maximum recommended dose is 100 mg as a single dose, not 60 mg daily.

Critical Clarification: What Are You Treating?

The answer depends entirely on why you're taking sildenafil 20 mg tablets:

If You're Taking It for Pulmonary Arterial Hypertension (PAH):

• The FDA-approved dose is 20 mg three times daily (60 mg total per day), taken 4-6 hours apart 1
• Do not increase beyond this dose—clinical trials showed no greater efficacy with higher doses for PAH 1
• Higher doses (above 20 mg TID) are specifically not recommended for PAH 1
• Research confirms that doses of 1,5, and 20 mg TID were studied, with 20 mg TID being most effective, but going higher provided no additional benefit 2

If You're Taking It for Erectile Dysfunction (ED):

You're using the wrong formulation and wrong dosing schedule. Here's what you need to know:

• Sildenafil for ED comes in 25 mg, 50 mg, and 100 mg tablets taken as needed, NOT three times daily 3
• The standard approach is to start at 50 mg, then titrate up to 100 mg if inadequate response 3, 4, 5
• Taking 20 mg tablets three times daily (60 mg total) is not the appropriate regimen for ED
• The maximum single dose for ED is 100 mg, taken approximately 1 hour before sexual activity 3

What To Do If Your Current Regimen Isn't Working

Before Increasing Any Dose, Evaluate These Common Causes of "Failure":

Most sildenafil "failures" are actually due to improper use 4, 6, 7:

1. Inadequate dosing: Many patients never tried the maximum recommended dose
2. Wrong timing: Taking the pill immediately before sex (need 30-60 minutes) or with a large meal (reduces absorption) 6
3. Lack of sexual stimulation: The medication requires sexual arousal to work 3
4. Insufficient trial: Need at least 4-8 attempts at maximum dose before declaring failure 6
5. No follow-up: 66% of "non-responders" in one study had never received proper instructions 6

After proper education and dose optimization, 31-55% of initial "non-responders" actually respond successfully 6, 7.

The Correct Approach for ED Treatment:

If you're treating ED, you need to switch to the proper formulation and dosing strategy 5:

1. Start with sildenafil 50 mg as a single dose, taken 1 hour before sexual activity
2. If inadequate response after 4-8 attempts, increase to 100 mg 3, 5
3. Ensure you're taking it on an empty stomach or with a light meal
4. Ensure adequate sexual stimulation
5. Avoid heavy alcohol use

Research shows that titrating from 50 mg to 100 mg provides significantly greater improvement in erectile function with no increase in adverse events 8.

If Maximum Dose Sildenafil Still Doesn't Work:

After an adequate trial at maximum dose (100 mg for ED, 20 mg TID for PAH), consider 4, 5:

• Different PDE5 inhibitor (tadalafil, vardenafil, avanafil)—some patients respond better to alternatives
• Check testosterone levels—if low, combining testosterone therapy with PDE5 inhibitors is more effective than either alone 5
• Address modifiable risk factors: diabetes control, hypertension, smoking cessation, relationship issues 4
• Second-line therapies: intraurethral alprostadil, intracavernosal injections, vacuum devices 4
• Third-line therapy: penile prosthesis 4

Safety Considerations

Do not increase doses on your own 1:

• Higher doses increase risk of adverse effects (headache, flushing, hypotension, visual disturbances)
• Absolute contraindication: Never use with nitrates (can cause life-threatening hypotension) 1
• Use caution with severe liver or kidney disease 5

Bottom Line

Talk to your prescribing physician immediately. You're either:

1. Taking the wrong formulation/schedule for ED (need to switch to 50-100 mg as-needed dosing), OR
2. At maximum dose for PAH (60 mg daily) and need alternative strategies rather than dose escalation

Do not self-escalate your dose—the solution likely involves proper dosing strategy, addressing modifiable factors, or switching to alternative therapies, not simply taking more of the same medication 4, 5, 6.