First: was it actually a fair trial?

Studies of men labelled as non-responders have repeatedly found that a large share succeed after nothing more than instruction on how to take the drug properly. Work through this before accepting a failure.

  • Did you allow enough time? Sildenafil and vardenafil need 30–60 minutes; tadalafil at least 30; avanafil 15–30.
  • Was your stomach relatively empty? A high-fat meal can delay sildenafil by well over an hour.
  • Was there genuine physical sexual stimulation? These drugs amplify a signal — they do not create one.
  • Had you been drinking? Alcohol impairs erections independently and adds to the side effects.
  • Did you try at least four to eight separate occasions before judging it?
  • Were you ever moved up from the starting dose? Many men are left on 50 mg sildenafil indefinitely.
  • Did the medication come from a licensed pharmacy? See counterfeit medication.

The escalation sequence

What to do, in order
StepActionGive it
1Correct technique and timing. Repeat the same dose properly.4–8 attempts
2Increase to the maximum tolerated dose with your prescriber.4–8 attempts
3Check testosterone (two morning samples), thyroid and prolactin. Correct if abnormal.Weeks to months
4Review every medication for contributors — especially antihypertensives and antidepressants.Weeks after any switch
5Switch to a different PDE5 inhibitor. Tadalafil if you were on sildenafil, or avanafil if side effects were the barrier.4–8 attempts
6Try daily low-dose tadalafil rather than on-demand dosing — the change in pattern helps some men, particularly where anxiety is involved.At least 4 weeks
7Add psychological treatment. Combination outperforms either alone.6–20 sessions
8Referral to urology for second-line treatment.

Second-line: what works when tablets do not

This is the part men do not know about, and it is the reason giving up is premature. Second-line treatments do not depend on the same mechanism, so failure of tablets tells you very little about whether these will work.

Injection therapy
Success rates of 70% to over 90%, including in men for whom tablets did nothing, because it acts directly on the erectile tissue and bypasses the nerve signal entirely. The needle is the barrier, not the effectiveness. See penile injections.
Vacuum erection device
Works mechanically, independent of nerves, arteries and hormones. Around 90% can achieve a usable erection; the honest caveat is that long-term satisfaction is lower. See vacuum devices.
Intraurethral alprostadil
Needle-free, but meaningfully less effective than injections. Reasonable if the needle is an absolute barrier. See MUSE.
Combination therapy
Under specialist supervision, a PDE5 inhibitor plus a vacuum device, or injections plus a constriction ring, can work where either alone does not. Only with guidance.

Third-line, and when to consider it

A penile implant has the highest satisfaction rate of any ED treatment — consistently 90–95% — and is frequently covered by insurance once conservative treatment has documented failure.

The trade-off is real and permanent: implantation ends the possibility of natural erections and of drug or injection therapy. That is exactly why it sits last in the sequence, and why documenting the earlier steps matters both clinically and for insurance approval.

And reconsider the diagnosis

Persistent non-response is also a prompt to ask whether the original assessment was complete.

  • Has cardiovascular risk actually been assessed, or only assumed? See ED and heart disease.
  • Has testosterone been measured properly — two morning samples — and were LH and prolactin checked if it was low?
  • Is there penile curvature, pain or a palpable lump suggesting Peyronie's disease?
  • Is sleep apnoea in the picture? It is the most commonly missed contributor.
  • Is the real problem low desire rather than erectile capacity? Those need different treatment.
  • Is depression or relationship distress the dominant factor?
FAQ

Frequently asked questions

How many times should I try before saying it doesn't work?
Four to eight separate attempts at the maximum tolerated dose, taken correctly and with genuine sexual stimulation.
If Viagra doesn't work, will Cialis?
Sometimes, and switching molecules is standard practice before moving on. Some men respond considerably better to one than the other for reasons that are not well understood.
What is the success rate of injections if tablets failed?
Typically 70% to over 90%, because injections act directly on the erectile tissue rather than amplifying a nerve signal.
Can I take a higher dose than prescribed?
No. Exceeding the maximum increases side effects and risk without improving results. Ask your prescriber about a dose increase instead.
When should I see a urologist?
After two different PDE5 inhibitors have failed at maximum tolerated dose with adequate trials — or sooner if you have penile curvature, pain, or ED following prostate surgery.
Sources

What this is based on

We link to primary sources — clinical guidelines, regulator publications and peer-reviewed research — wherever possible. Links open on third-party sites we do not control.

  1. [01]American Urological Association. Erectile Dysfunction: AUA Guideline (2018).
  2. [02]National Institute of Diabetes and Digestive and Kidney Diseases. Treatment for Erectile Dysfunction.
  3. [03]Urology Care Foundation. What is Erectile Dysfunction?.
  4. [04]U.S. Food and Drug Administration. Drugs@FDA — approved drug products and prescribing information.