ED is common, and very treatable. The physical and emotional causes, why it can be an early warning sign for heart disease, and how sildenafil, tadalafil and other treatments work.
What is erectile dysfunction?
Erectile dysfunction (ED) means having trouble getting or keeping an erection firm enough for sex. Almost every man has trouble now and then – that's normal. It's called ED when it happens regularly.
ED is very common: it affects an estimated 30 million men in the US. It becomes more common with age, but it isn't an inevitable part of getting older, and it can almost always be treated.
Common causes
An erection depends on healthy blood vessels, nerves, hormones and state of mind, so many things can get in the way – and often it's more than one.
Physical causes:
- Narrowed blood vessels (atherosclerosis), high blood pressure and high cholesterol
- Type 2 diabetes
- Being overweight, and too little exercise
- Smoking and heavy drinking
- Low testosterone
- Nerve damage, for example after prostate surgery or a spinal injury
- Sleep apnea
- Some medicines, including certain antidepressants and blood pressure medicines, and recreational drugs
Emotional causes:
- Stress and anxiety, including worry about performance
- Depression
- Relationship problems
ED and your heart
ED can be an early warning sign of heart disease. The arteries that supply the penis are smaller than those to the heart, so narrowing can show up there first – sometimes years before a heart attack or stroke. That's why it's worth seeing a doctor about ED rather than only treating it: a check of your blood pressure, cholesterol and blood sugar could pick up a problem early.
Treatments that work
Lifestyle changes – exercising, losing weight, stopping smoking, drinking less and sleeping better – can improve erections, and help any other treatment work better.
Prescription tablets (PDE5 inhibitors) are the most common treatment. They increase blood flow to the penis, and only work when you're sexually aroused:
| Medicine | When to take it | How long it works |
|---|---|---|
| Sildenafil (Viagra) | About 1 hour before sex; a heavy, fatty meal can delay it | About 4–5 hours |
| Tadalafil (Cialis) | 30 minutes to 2 hours before sex, or a low dose every day | Up to 36 hours |
| Vardenafil (Levitra) | About 1 hour before sex | About 4–5 hours |
Our guide to sildenafil, tadalafil and vardenafil compares them in more detail.
Safety:
- Never take them with nitrates (such as nitroglycerin for chest pain) or riociguat – together they can cause a dangerous drop in blood pressure.
- Tell your doctor about all your medicines, including alpha-blockers for blood pressure or the prostate.
- Get emergency help for an erection that lasts more than 4 hours, or sudden loss of vision or hearing.
Other options include vacuum devices, injections or pellets of alprostadil, testosterone treatment if blood tests confirm it's low, counseling or sex therapy, and penile implants.
Buying ED medicine safely
Only use FDA-approved medicines from a licensed pharmacy. "Herbal Viagra" supplements and brands made for markets outside the US are not FDA-approved – the FDA has repeatedly found hidden prescription drugs in so-called natural ED products. Our guide to Kamagra, Cenforce and Fildena explains the risks. PharmacyFarm dispenses ED medicines only after our pharmacist has verified your prescription.
When to see a doctor
See a doctor if ED lasts more than a few weeks, worries you or your partner, started after surgery or an injury, or comes with low sex drive, pain or a bend in the penis. Call 911 if you have chest pain or shortness of breath, especially during sex.