Erectile dysfunction

It affects one man in two after fifty, and a growing number of young men. It is rarely “all in the head”: it is often the first visible sign of a vascular problem, and it can be treated.

What is being described

Erectile dysfunction is the repeated inability, over at least three months, to get or keep an erection sufficient for satisfactory sex. The important word is repeated: an occasional failure after a heavy evening, a short night or a stressful period has no diagnostic value and happens to everyone. What counts is consistency and impact.

Frequency rises with age — around 10 % at forty, half of men after seventy — but the commonest reason for consulting today involves men under forty, in whom the mechanism is rarely the same.

Erection, in three lines

An erection is a vascular event under nervous control. Arousal releases a messenger, nitric oxide, which relaxes the smooth muscle of the penile arteries. Blood enters, the corpora fill, venous outflow closes. Anything that damages arteries, nerves, hormonal balance or the brain's command can interrupt that chain.

Causes, in order of frequency

The sign that points the way

Spontaneous nocturnal and morning erections, and normal erections with masturbation, point to a psychological or relational cause. Their complete disappearance points to an organic one. Abrupt onset after a specific event is more likely psychological; gradual decline over months is more likely vascular.

The minimum work-up

It is simple and should not be skipped: blood pressure, waist, blood glucose, lipids, a morning testosterone if desire has fallen, genital examination, a full review of medicines taken. In men over forty, cardiovascular risk assessment is essential. Many men consult about erections and leave with a diagnosis of diabetes or hypertension: that is a benefit, not a setback.

What helps without a prescription

Three interventions have measured effects: stopping smoking, regular physical activity — aerobic exercise improves erectile function with an effect comparable to a drug in sedentary men — and weight loss where there is excess. Treating sleep apnoea, where present, also clearly helps. These act over weeks to months, and they improve cardiovascular risk at the same time.

PDE5 inhibitors: sildenafil and the rest

Sildenafil — marketed as Viagra and, since the patent expired, as many generics — was discovered by accident: it was being studied as a treatment for angina. It belongs to the phosphodiesterase type 5 inhibitors, which stop the breakdown of the messenger released by arousal. Hence a poorly understood point: they do not create desire and trigger nothing on their own. Without sexual stimulation nothing happens. A tablet taken “to see”, without arousal, gives the impression the treatment does not work.

Effectiveness is real — around two thirds to three quarters of men respond — but lower with long-standing diabetes or after prostatectomy. Four attempts at an adequate dose are needed before concluding failure.

Side effects and contraindications

The commonest effects are mild: headache, flushing, blocked nose, indigestion, muscle aches with tadalafil, a slight blue tinge to vision with sildenafil.

Combinations that are forbidden

  • Nitrates prescribed for angina — glyceryl trinitrate, isosorbide — in every form, including the emergency spray. The drop in blood pressure can be fatal. A man taking nitrates must not take sildenafil, and vice versa.
  • Poppers, which are also nitric oxide donors. This is the commonest accident in party settings, because both circulate at the same events.
  • Some pulmonary hypertension treatments and alpha blockers prescribed for the prostate, which need close supervision.

Other interactions matter: azole antifungals, some macrolide antibiotics and antiretrovirals strongly raise concentrations and require a reduced dose; grapefruit does the same. The doctor must know everything being taken.

A consultation is needed before considering these treatments after a recent heart attack or stroke, with unstable angina, severe heart failure, low blood pressure, poorly controlled arrhythmia, inherited retinal disease or a history of ischaemic optic neuropathy. A painful erection lasting more than four hours — priapism — is a surgical emergency: delay causes permanent damage.

The other treatments

Buying online: the trap

Sildenafil is among the most counterfeited medicines in the world. Analyses of seized tablets regularly find wrong doses, active ingredient absent or in excess, and contaminants: plaster, printing ink, amphetamines, antidiabetics. The risk is not only the product: it is the absence of any examination. Buying online also means forgoing the cardiovascular assessment that would have caught the hypertension or diabetes behind the symptom.

Where can you get it without a prescription?

Almost nowhere. Four countries have opened a route without a doctor's prescription, and always through a pharmacy consultation: the United Kingdom since 2018 (sildenafil 50 mg, sold as Viagra Connect), Poland since May 2016, New Zealand since 2014 — through a specifically trained pharmacist, and only for men aged 35 to 70 — and Norway since August 2019.

Everywhere else a prescription remains compulsory for every PDE5 inhibitor. A website offering sildenafil without a prescription from one of those four countries is not thereby allowed to ship it to you: the rule that applies is the one where you live.

Price and reimbursement vary widely. Sildenafil generics cost a fraction of the brand, and no health system covers these treatments outside narrow indications unrelated to ordinary erectile dysfunction.

Talking about it in the couple

Silence does more damage than the symptom. With no explanation, the partner almost always reads the failure as lost desire for them, and performance anxiety installs on both sides. Simply saying that this is a medical problem being investigated defuses most of that misunderstanding.

← Back : Sexuality

Page checked in September 2026. The instruments cited can change: if in doubt, confirm with the official source given.

Who to see for this problem?

The page Who to see, and when gives, symptom by symptom, the right professional — family doctor, urologist, gynaecologist, sex therapist, psychologist — and the emergencies that cannot wait.

Test what you have just read

Five questions, and every answer is somewhere on this page. Nothing is recorded: the score stays in your browser.

Loading the quiz…

Locate this page in the site map

A question, a correction, a suggestion? Write to us.