Prostate enlargement, also known as benign prostatic hyperplasia (BPH), and erectile dysfunction (ED) are separate problems. Both increase with age, but one causes problems in the bathroom and the other in the bedroom. However, the two are somewhat linked.
BPH happens when your prostate becomes enlarged, but cancer is not the cause. A man’s prostate continues growing throughout most of his adult life. This is why many older men are affected by the condition.
ED is the inability to get or maintain an erection. It can be caused by physical conditions such as heart disease, low testosterone, and diabetes. It can also be caused by psychological issues.
These two conditions don’t necessarily seem linked, but certain treatments that relieve BPH can cause ED and other sexual side effects. On the other hand, treating ED can improve enlarged prostate symptoms.
Prostate enlargement can interfere with urination. It can cause sudden side effects including:
- urges to urinate
- frequent urination
- inability to empty the bladder
- a weak urine stream
A surgery called transurethral resection of the prostate (TURP) can help relieve these symptoms. Men who have this procedure often experience sexual side effects after surgery.
Between 50 and 75 percent of men experience retrograde ejaculation after TURP, according to Harvard Medical School. This means that semen released during orgasm enters the bladder rather than exiting the penis. Retrograde ejaculation is sometimes called dry orgasm. It’s not harmful but can affect male fertility.
Some men who undergo the TURP procedure also experience ED. This isn’t a common side effect of the surgery, but does occur in 5 to 10 percent of men.
Some drugs used to treat BPH can cause difficulty in maintaining an erection. Men who take alpha-blockers such as doxazosin (Cardura) and terazosin (Hytrin) may experience decreased ejaculation. This is because alpha-blockers relax bladder and prostate muscle cells.
Alpha reductase inhibitors can also cause ED. Additionally, reduced sex drive is a possible side effect of the BPH medications dutasteride and finasteride, which are both alpha reductase inhibitors. Approximately 3 percent of men who took dutasteride (Avodart) experienced a drop in libido. About 6.4 percent experienced low libido with finasteride (Proscar). The drug combination of dutasteride and tamsulosin (Jalyn) is associated with low libido in 4.5 percent of men who take it.
Men who take these medications may also experience lower sperm count, decreased sperm volume, and lower sperm movement.
Medications that treat erectile dysfunction may help improve BPH. ED drugs sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) have all been shown to reduce BPH symptoms. However, they aren’t currently approved to treat BPH.
These medications inhibit a protein that breaks down a chemical called cyclic guanosine monophosphate (cGMP); cGMP increases blood flow to the penis. By inhibiting the protein that breaks down cGMP, blood flow to the penis can be increased.
In theory, ED drugs can boost cGMP levels in the bladder and prostate as well. The increased cGMP and blood flow may allow bladder and prostate cells to relax, leading to greater urinary flow.
One study comparing tadalafil and placebo showed that men who took 5 mg of tadalafil daily had significant improvement in both BPH and ED symptom measures.
In another trial, 108 men who took 10 mg of vardenafil twice daily showed significant improvement in prostate symptoms compared with 113 men who took a placebo. The men were 45 to 64 years old and had a history of BPH.
The study also included men who had ED. The results showed improvement in both BPH and ED symptoms in men who had both conditions.
The studies on ED medication and its ability to relieve enlarged prostate symptoms have only looked at short periods of time. They have also only looked at the differences between ED medications and placebo. The results show promise, but the data is not long-term. The studies have not fully shown that ED drugs are safe and effective to treat urinary symptoms of enlarged prostate. More evidence is needed from studies that directly compare erectile dysfunction drugs with medications for BPH.
Erectile dysfunction medications and alpha-blockers both lower your blood pressure. If you are taking both ED and BPH medications, your doctor may recommend taking them at different times of the day to avoid dizziness or a steep drop in blood pressure.
Your doctor may also be able to recommend lifestyle changes and exercises that can help improve your condition.