In short
The four standard tablets work about equally well. What separates them is onset, duration and how food affects them.
| Drug | Timing and duration |
|---|---|
| Sildenafil | Take 60 minutes before. Lasts 4 to 5 hours. The longest safety record |
| Vardenafil | 60 minutes, or 30 for the dissolving form. Lasts 4 to 5 hours |
| Tadalafil | Effective up to 36 hours. Also available as a low daily dose |
| Avanafil | As little as 15 minutes before. Lasts 4 to 5 hours |
Successful intercourse in 68 to 69 percent of men against 33 to 35 percent on placebo. All four need a prescription in the UAE, and most of what is sold without one is not what the label says.
Treatment Overview
How well do they work?
Well. Across the four drugs, successful intercourse rates are 68 to 69 percent compared with 33 to 35 percent on placebo.
For sildenafil specifically, a meta-analysis of 27 trials in 6,659 men found successful intercourse in 57 percent against 21 percent on placebo. They also work in men with diabetes and after nerve sparing prostate surgery, although less well after non nerve sparing surgery.
The certainty of the evidence comparing the four drugs directly is low, which is why the choice below is made on how you live rather than on a ranking.
How to actually take them
- On an empty stomach for maximum effect, although they can be taken with food
- Timing differs. Sildenafil tablet, vardenafil and tadalafil at 60 minutes. Avanafil, dissolving vardenafil and sildenafil oral film at 30 minutes or less
- They need arousal. They do not produce an erection on their own, and without sufficient sexual stimulation they will not work
- A high fat meal delays sildenafil and lowers the peak level of vardenafil by about 18 percent. It does not affect tadalafil
Retrying with proper instruction rescues about 25 to 30 percent of men previously labelled as non-responders. That is worth knowing before concluding that the treatment failed.
Choosing between them
The choice comes down to your preferences: cost, ease of use, how long you want it to last, and side effects.
- Want spontaneity: tadalafil, effective up to 36 hours, or a low daily dose which removes the timing question entirely
- Want speed: avanafil, the only one approved for onset as early as 15 minutes
- Want the longest track record: sildenafil
- Eating first: tadalafil and dissolving vardenafil are not delayed by a high fat meal
Daily dosing
Low dose daily tadalafil, at 2.5 or 5 mg, works about as well as higher on demand doses, and the 5 mg dose is more effective than 2.5 mg.
In one trial of 268 men, daily tadalafil produced successful penetration in 36 to 39 percent against 11 percent on placebo, successful intercourse in 45 to 50 percent against 13 percent, and no erectile dysfunction at all in 50 percent against 8 percent.
It can be continued indefinitely, may suit men who also have prostate related urinary symptoms, and is avoided where kidney function is below a creatinine clearance of 30.
What if tablets are not enough?
There is a defined order, and it starts with the least invasive option.
- A vacuum erection device first, being non invasive and less expensive. These produce an erection in as many as 60 to 70 percent of men, and should not be left in place for more than 30 minutes
- Penile self injection with alprostadil, or intraurethral alprostadil
- A penile implant for men who cannot use or have not responded to anything else
Before moving down that list, it is worth checking that the tablet was actually taken correctly, on an empty stomach, at the right interval and with arousal. What the first review covers.
Where testosterone fits
Where testosterone is unequivocally low, it is added to a PDE5 inhibitor rather than used instead of one. Testosterone alone improves desire reliably but is less effective for erections.
The combination appears most useful in men with low testosterone who did not respond to a PDE5 inhibitor alone, and the largest gains were in men with more severe deficiency. What testosterone does and does not improve.
ED medication in Dubai and the UAE
What is actually in products sold for sexual performance?
Often a prescription drug that is not on the label. Current studies suggest that between one third and one half of supplements sold as natural products for sexual enhancement contain synthetic chemicals, most commonly PDE5 inhibitors or close analogues of them.
The UAE Ministry of Health and Prevention has warned publicly about sexual enhancement products containing undeclared sildenafil, vardenafil, tadalafil and dapoxetine, naming a severe fall in blood pressure as the main danger, particularly for anyone taking nitrates.
The scale is not small. The World Health Organization reported that 37 percent of counterfeit medication involved the genitourinary area, and in one national seizure of 1,283 packages of counterfeit or unlicensed health products, 98 percent were sexual enhancement products. Regulators publish running lists of the products found to be adulterated.
Do these tablets need a prescription here?
Yes. PDE5 inhibitors are prescription medicines under the Dubai Health Authority drug classification, and a licensed pharmacy will ask for one.
A regional survey found that 84.1 percent of men using these drugs had obtained them without a prescription, and only 38.1 percent of the users actually had erectile dysfunction (UAE expert panel review, 2025). The prescription is not paperwork. It is the step where nitrates, alpha blockers and cardiac risk get checked.
What about what you read online?
Treat it carefully. The same UAE review cited an analysis finding that 84 percent of widely viewed Arabic-language social media content about erectile dysfunction was not based on scientific evidence.
The two most used tablets in detail: Sildenafil (Viagra) and Tadalafil (Cialis). Early ejaculation as well? Premature ejaculation treatment. Not sure how severe the problem is? Take the 1-minute erection check.
Who Is a Good Candidate?
- Your cause has been assessed and your cardiac risk is low
- You have tried a tablet without proper instruction on timing and use
- You want a treatment that fits how you actually live rather than the first one on the list
- You have both erectile dysfunction and prostate related urinary symptoms
- Tablets have not worked and you want to know what the next options are
- You take nitrates in any form, regularly or occasionally. This is an absolute contraindication
- You take an alpha blocker, which needs the dose and timing adjusted rather than ruling treatment out
- Sudden loss of vision or hearing after taking a dose, which needs immediate assessment
What Happens During the Consultation
-
1
Confirming it is safe
Nitrates in any form are an absolute contraindication. Alpha blockers need care because of the risk of low blood pressure. Cardiac risk must already have been graded, and high risk needs cardiology review first.
-
2
Matching the drug to your life
Onset, duration, whether you eat before, and cost. Tadalafil for spontaneity or as a daily dose, avanafil for speed, sildenafil for the longest track record.
-
3
Instruction that is part of the prescription
Empty stomach, correct timing for the drug chosen, and the fact that arousal is still required. This alone rescues a quarter to a third of apparent treatment failures.
-
4
A baseline and a review
A validated score before treatment, so improvement is a defined change rather than an impression, and a review to adjust dose or switch drug before concluding anything has failed.
Program Structure & Follow-Up
The first weeks
- Start at the standard dose: sildenafil 50 mg, tadalafil 10 mg on demand or 5 mg daily, avanafil 100 mg
- If tolerated but not fully effective, the dose goes up before the drug is changed
- If not tolerated, a different drug in the same class often suits better
Measuring the result
Against a validated score rather than an impression. What counts as a meaningful improvement.
Side effects, in proportion
Most are mild, short lived and dose related. The table gives the common ones with how often they occur.
| Effect | How often |
|---|---|
| Flushing | About 12 percent |
| Headache | About 11 percent |
| Indigestion | About 5 percent |
| Nasal congestion | Reported, less common |
| Blue tinged vision | Occasional, with sildenafil only. Lasts two to three hours and resolves on its own |
The rare ones worth knowing
A form of optic nerve damage has been reported, and the risk appears raised even after allowing for shared risk factors such as age, blood pressure, cholesterol and diabetes. Serious retinal problems have also been reported. The absolute risk of any of these is very low, at 2 to 4 cases per 10,000 person years.
Sudden hearing loss has been reported rarely, usually in one ear, within the first 24 hours, and it was temporary in about a third of cases.
Any visual or hearing symptom needs prompt assessment. Routine eye monitoring is not recommended in men without symptoms or known retinal disease.
Benefits, Limits & Safety
Realistic expectations
These drugs restore function in most men. They do not increase desire, and they do not work without arousal. A man whose problem is low desire rather than erections will not be helped by them.
Low desire is treated by finding its cause, because almost every cause has a specific treatment of its own. Treatment by cause.
They also do not treat the cause. Where the cause is vascular, the cardiovascular risk still needs managing in its own right. Why that is assessed first.
What improves the odds alongside medication
- Aerobic exercise, which improved erectile function against placebo in a meta-analysis of 11 trials
- Weight loss, including after bariatric surgery, which also raises testosterone
- Stopping smoking
- Treating sleep apnoea, which improved erectile function in some studies
- Reviewing antidepressants and blood pressure medication
The absolute limits
Nitrates in any form, whether taken regularly or occasionally, rule these drugs out completely. Because of tadalafil’s longer half life, it is suggested that nitrates be avoided for at least 48 hours after the last dose.
Alpha blockers require caution because of the risk of a sharp fall in blood pressure, and avanafil is started at the lower dose in men taking one.
An honest note on melanoma
Some studies reported a small association between PDE5 use and melanoma. A further study concluded it was unlikely to be causal, since greater exposure was not linked to higher risk and men taking these drugs had more sun exposure. It is worth knowing about rather than worrying about.
They work well
Successful intercourse in 68 to 69 per cent of men against 33 to 35 per cent on placebo, and comparable results in men with diabetes.
Dose before drug
If tolerated but not fully effective, the dose goes up before the drug is changed. Improvement is measured against a validated baseline score.
Absolute and relative
Nitrates in any form are absolute. Alpha blockers need care. Any sudden visual or hearing symptom needs prompt assessment.
Cost & Program Investment
The consultation is quoted individually, and the medication is an ordinary prescription bought from a pharmacy at pharmacy prices, which usually costs less than the online services selling the same molecules. There is no subscription and no minimum course. Second line options, if they become relevant, are quoted before they are arranged.
Frequently Asked Questions
None of the four is clearly better than the others for effectiveness, and the certainty of the evidence comparing them is low. The choice is made on timing and convenience: tadalafil for spontaneity over up to 36 hours, avanafil for onset as early as 15 minutes, sildenafil for the longest track record.
Not yet. Proper instruction on timing, an empty stomach and the need for arousal rescues about 25 to 30 percent of men previously labelled as non-responders. After that the dose is increased, then a different drug in the same class is tried.
Tadalafil is available as a low daily dose of 2.5 or 5 mg. In one trial of 268 men, daily tadalafil produced successful intercourse in 45 to 50 percent against 13 percent on placebo and resolved erectile dysfunction entirely in 50 percent against 8 percent. It is avoided where kidney function is below a creatinine clearance of 30.
Not with nitrates, in any form, regularly or occasionally. That is an absolute contraindication because the combination can cause a severe fall in blood pressure, and with tadalafil nitrates should be avoided for at least 48 hours after the last dose. Alpha blockers need caution rather than exclusion.
Flushing in about 12 percent, headache in about 11 percent, indigestion in about 5 percent, and nasal congestion less often. Sildenafil occasionally causes a blue tinge to vision that lasts two to three hours and resolves on its own. Any sudden visual or hearing symptom needs prompt assessment.
Only if it is genuinely low on repeated morning testing. Where it is, testosterone is added to a PDE5 inhibitor rather than used instead of one, because testosterone alone improves desire more reliably than it improves erections.
No, and that is the problem. Between one third and one half of supplements sold as natural sexual enhancers have been found to contain undeclared synthetic PDE5 inhibitors or analogues, and the UAE Ministry of Health and Prevention has warned about exactly this. The danger is a severe drop in blood pressure, especially in anyone taking nitrates.
Yes. PDE5 inhibitors are prescription medicines under the Dubai Health Authority classification. In a regional survey 84.1 percent of users had obtained them without one, which means nobody checked their nitrates, their alpha blockers or their cardiac risk.
Evidence
Where this information comes from
Every figure on this page is taken from the sources below. All of them are free to read, so you can check them yourself.
- Sildenafil for male erectile dysfunction: a systematic review and meta-analysis
- Erectile dysfunction: expert panel recommendations for the UAE, full text
- Do not consume sexual enhancement pills, warns UAE health ministry
- Tainted sexual enhancement products
- Drug control
- EAU guidelines on sexual and reproductive health
- Association of erectile dysfunction and cardiovascular disease: an umbrella review of systematic reviews and meta-analyses
This page is general medical information and does not replace a personal consultation. Trial results are averages across large groups, not a prediction for any one person.