Avodart (dutasteride) and Proscar (finasteride) are both members of the drug class known as 5-alpha-reductase inhibitors and are best known as treatments for benign prostatic hyperplasia, aka enlarged prostate. Since both drugs are in the same class, how do doctors and patients choose which one would be best as a treatment option? This article compares Avodart and Proscar for enlarged prostate and lets you and your physician make the choice.
All 5-alpha-reductase inhibitors work by inhibiting an enzyme that transforms testosterone into dihydrotestosterone, a hormone that can lead to an enlarged prostate. In addition to Avodart and Proscar, another drug in this category is Propecia (which is used to treat hair loss). Jalyn is a combination drug that contains both dutasteride and tamsulosin, an alpha-adrenergic blocker that also is prescribed to treat an enlarged prostate.
Study comparing Avodart and Proscar
The Enlarged Prostate International Comparator study (EPICS) compared the effectiveness and occurrence of side effects associated with use of Avodart and Proscar. During the multicenter, randomized, double-blind, 12-month study, 813 men received once-daily treatment with dutasteride (0.5 mg) and 817 took finasteride (5 mg).
At the end of the study, the investigators found that:
- Both dutasteride and finasteride were similarly effective at reducing prostate volume
- Both drugs resulted in similar symptom relief, such as urinary frequency, starting and stopping urination, urinary urgency, and weak urine stream
- The percentage of side effects experienced by patients was similar between both groups of patients (see below)
What are side effects of Avodart and Proscar for enlarged prostate?
Both Avodart and Proscar have similar side effects. They include the following:
- Erectile dysfunction
- Low libido
- Reduced sexual arousal
- Difficulties with orgasm
- Abnormal ejaculation
- Testicular pain
- Risk of high-grade prostate cancer
- Swelling of hands or feet
- Skin rash
- Runny nose
- Feeling faint
- Swelling or tenderness in the breast
These two drugs, as well as Propecia and Jalyn (which is a combination of dutasteride and the alpha-blocker tamsulosin), are also associated with an increased risk of developing high-grade prostate cancer. The Food and Drug Administration issued a safety warning in 2011 to this effect, so all of these drugs must display a warning box on their labels.
What else should you know about Avodart and Proscar for enlarged prostate?
Avodart and Proscar share other characteristics; for example, both are available in oral forms, are taken once daily, and have generic products available. Because insurance plans typically cover only one drug in any given category, men should check to see which drug is accepted by their plan. Otherwise, choosing between Avodart and Proscar is up to the patient and his doctor to determine.
Read more in our BPH Health Center.
Nickel JC et al. Comparison of dutasteride and finasteride for treating benign prostatic hyperplasia: the Enlarged Prostate International Comparator study (EPICS). BJU International 2011 Aug; 108(3): 388-94