Erectile Dysfunction

Erectile Dysfunction Medication

What is Erectile Dysfunction?

Erectile dysfunction (ED) is a medical condition characterized by the inability to initiate or maintain an erection.  It is commonly caused by psychological factors in young healthy men but may be due to underlying conditions such as obesity, hypogonadism, diabetes, peripheral vascular disease, or spinal problems in older adults.

Erectile dysfunction is an exceedingly common condition, especially in elderly males.  Individuals may have preserved sexual desire but cannot sexually perform to their partner’s satisfaction – this may lead to self-consciousness and reduced confidence.  First-line medications are often helpful in alleviating symptoms but occasionally more invasive strategies are employed for patients with refractory cases.

What Causes Erectile Dysfunction?

Erectile dysfunction can be caused by a variety of conditions.  In young healthy men, it is typically related to psychological factors such as “performance anxiety.”  In older men with underlying medication problems, the erectile dysfunction may be related to one or more of the following conditions:

  • Obesity
  • Smoking
  • Hypogonadism – low testosterone levels
  • Diabetes – results in nerve and blood vessel damage
  • Peripheral vascular disease – reduced blood and oxygen supply
  • Spinal disease – damaged nerves

It can also be caused by alcohol use or certain medications such as benzodiazepines (eg, Valium), antihypertensives (eg, beta blockers, thiazide diuretics), and antidepressants (eg, SSRIs and tricyclic agents).

How Common is Erectile Dysfunction?

Erectile dysfunction is exceedingly common in the United States and often evaluated in primary care clinics.  Advanced cases of this condition regularly require referral to a Urology specialist – this is especially true of cases that do not respond to first-line treatment measures.

The most common sexual problem in men is erectile dysfunction.  A multinational study of almost 30,000 men demonstrated a 16% prevalence of erectile dysfunction.  In this study, 8% of men with erectile dysfunction were age 20-30, whereas 37% of men were age 70-75.

Signs and Symptoms

Symptoms of erectile dysfunction often include:

  • Inability to initiate an erection
  • Impaired ability to maintain an erection
  • Trouble ejaculating
  • Absence of spontaneous morning erections

Patients with spine disease may have muscle weakness, numbness, in tingling in the lower extremities.  In severe cases, patients will be paraplegic or quadriplegic.  Patients with poorly controlled diabetes may have loss of sensation and poor circulation on physical examination.  They may also have polyuria (increased urination), polydipsia (excessive thirst), and polyphagia (excessive hunger).  Those with hypogonadism may have fatigue and decreased sexual desire.


The diagnosis of erectile dysfunction is suggested based on symptoms.  Physical examination and laboratory testing are often performed to determine the cause of symptoms.

Your doctor will usually order testosterone levels – these are typically obtained first thing in the morning.  Other commonly ordered blood tests include a CMP (comprehensive metabolic panel), CBC (complete blood cell count), and thyroid function (TSH, free T4).  They may also check your fasting cholesterol levels and screen you for diabetes.

On physical examination, your doctor will typically look for abnormalities in the appearance of the external genitalia, presence of pubic hair, and testicular size.  They will also typically examine the back and perform a neurologic evaluation for leg weakness, sensory loss, and hyperreflexia.  Your doctor may also examine for the cremasteric reflex in which they brush a Q-tip against the inner thigh and observe for ascent of the testicle in the scrotum.  Your doctor may also perform a rectal examination to check for rectal tone, prostate size, prostate and contour.

Erectile Dysfunction Medication and Treatment

Erectile dysfunction is first treated by reversing any underlying conditions that may be contributing to symptoms.  This include optimizing glucose control in diabetics, improving cholesterol levels, tobacco cessation, reversing spinal disease, supplementing testosterone in patients that are deficient, and discontinuing alcohol and certain medications.

Patients may also benefit from a class of medications are called phosphodiesterase-5 (PDE-5) inhibitors - these work by promoting engorgement of the penis via vasodilation.  The most commonly prescribed agents include:

Patients that do not respond to the above measures may benefit from self-injection of intracavernous therapy such as Muse (alprostadil). Patients that have refractory symptoms despite these measures may be candidates for surgical implantation of penile prosthesis.


  1. McVary KT. Clinical practice. Erectile dysfunction. N Engl J Med 2007; 357:2472. -
  2. Selvin E, Burnett AL, Platz EA. Prevalence and risk factors for erectile dysfunction in the US. Am J Med 2007; 120:151. -

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.