Dutasteride side effects and benefits for hair growth and prostate gland enlargement
August 23 2016 by
Ray Sahelian, M.D.


Dutasteride (product name Avodart or Duprost) is a prescription drug used as a treatment to shrink benign prostatic hyperplasia in order to improve urinary symptoms, reduce the risk of acute urinary retention, and reduce the need for BPH-related surgical interventions. Dutasteride, being a 5alpha-reductase inhibitor, can also be effective for male pattern hair growth... but at a cost of potentially significant side effects.


Dutasteride side effects, safety, danger, risk, caution

The most common side effects of dutasteride include ear, nose, and throat infection; malaise; headache; dizziness; and musculoskeletal pain. Just as finasteride has the potential to interfere with sexuality and libido, it is possible that dutasteride may have similar sexual drive reducing potential. The main dutasteride sexual side effects are erectile dysfunction, decreased libido, gynacomastia and ejaculation disorders.


Reversal of the sexual numbing or erectile dysfunction can be accomplished with the use of natural sex enhancers such as reviewed in this article on natural aphrodisiacs.


Urology. 2014. Dutasteride on benign prostatic hyperplasia: a meta-analysis on randomized clinical trials in 6460 patients. Dutasteride therapy is related to an increased rate of sexual dysfunction.


Dutasteride and Prostate, testosterone level

Compared with placebo, dutasteride has been shown to significantly improve BPH symptoms, reduce the incidence of acute urinary retention and BPH-related surgery, and improve BPH-related quality of life. Few published data exist comparing dutasteride with finasteride. Clinical trials, sponsored primarily by the manufacturer, have shown dutasteride to be an effective treatment of prostate enlargement compared with placebo and to likely be similar to finasteride or Proscar. Further studies are needed to gain a more clear understanding of any clinically significant differences between dutasteride and finasteride.


Andrologia. 2014 Feb 6. Dutasteride in men receiving testosterone therapy: a randomised, double-blind study. We investigate the impact of dutasteride on prostate specific antigen (PSA) and prostate volume in men receiving testosterone (T) therapy. Twenty-three men on stable dose T therapy were randomised to receive either dutasteride or placebo for 12 months. Serum levels of PSA, T and dihydrotestosterone (DHT) and responses to the International Index of Erectile Function (IIEF) and Male Sexual Health Questionnaire (MSHQ) questionnaires were determined at baseline and at 3, 6, 9 and 12 months. Prostate volume (PV) was measured using transrectal ultrasound (TRUS) at baseline and again after 12 months. A total of 22 men (mean age 57.3) completed the study, with 11 men receiving placebo and 11 receiving dutasteride. Men receiving dutasteride had a significant decrease in PSA (-0.46 ± 0.81 ng ml-1 ; P = 0.04) and in PV (-6.65 ± 11.0%; P = 0.03) from baseline over 12 months. DHT decreased significantly for men on dutasteride compared with men receiving placebo. When compared with men who received placebo, men who received dutasteride demonstrated nonsignificant trends towards decreased PSA (-0.46 versus 0.21 ng ml-1 ; P = 0.11), PV (-6.65% versus 3.4%; P = 0.08) and MSHQ scores (-10.2 versus 5.6; P = 0.06). Dutasteride reduces PSA and PV for men on T therapy, but perhaps less so than in men without T therapy.


Dutasteride appears to be beneficial in treating benign prostatic hyperplasia (BPH). Dr. Francois Desgrandchamps of Hopital Saint Louis, Paris and associates note that dutasteride has done well in research trials, providing significant improvements in symptoms and urinary flow, and has led to significant reductions in prostate size and the need for surgery. In addition, dutasteride appeared to be well tolerated with few side effects. To find out if these benefits extended to patients in routine clinical practice, the researchers conducted a study with 366 men with BPH. All received dutasteride daily for 6 months. By the end of the study, 72 percent of patients had at least a 3-point reduction in the International Prostate Symptom Score, a standard measure of BPH symptoms. On average, the score fell from 15 at the start of the study to 10 at 12 weeks and to 9 after 24 weeks. Dutasteride appeared to be well tolerated. BJU International, July 2006.


How does Dutasteride Work?
Prostate growth is caused by a hormone in the blood called dihydrotestosterone (DHT). Dutasteride lowers DHT production in the body, leading to shrinkage of the enlarged prostate in most men. Dutasteride, is a dual 5alpha-reductase inhibitor for the treatment of benign prostatic hyperplasia. Dutasteride differs from finasteride as it inhibits both isoenzymes of 5alpha-reductase and results in near-complete suppression of serum dihydro-testosterone. Similar to finasteride, dutasteride reduces serum prostatic specific antigen by approximately 50% at 6 months and total prostate volume by 25% in 2 years. Randomised, placebo-controlled trials conducted over 2 years have shown the efficacy of dutasteride in symptomatic relief, and peak urinary flow rate, and reduction of acute urinary retention events and the need for surgery.  Dutasteride has been shown to possess tumor regression properties in vitro and its role in chemoprevention of prostate cancer is being evaluated in the ongoing Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial.


Dutasteride and Hair loss
Dutasteride is being tested for hair loss. Dutasteride has shown benefit in restoring hair to bald men. Dutasteride interferes with 5-alpha-reductase enzymes that break down the male hormone testosterone and turn it into dehydrotestosterone (DHT) - which causes hair to thin dramatically in later life. Dutasteride may have better DHT supression results than finasteride both Propecia and Proscar). Dutasteride has shown promise as a hair loss treatment for those with male pattern baldness. Dutasteride is developed by GlaxoSmithKline. Dutasteride is a dual 5-alpha-reductase inhibitor that is indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate. Dutasteride is currently in a trial phase for the treatment of male pattern baldness.


The importance of dual 5alpha-reductase inhibition in the treatment of male pattern hair loss: results of a randomized placebo-controlled study of dutasteride versus finasteride.
J Am Acad Dermatol. 2006.
Our aim was to evaluate the efficacy of the type 1 and 2 5alpha-reductase inhibitor dutasteride in men with male pattern hair loss. Four hundred sixteen men, 21 to 45 years old, were randomized to receive dutasteride 0.05, 0.1, 0.5 or 2.5 mg, finasteride 5 mg, or placebo daily for 24 weeks. Dutasteride increased target area hair count versus placebo in a dose-dependent fashion and dutasteride 2.5 mg was superior to finasteride at 12 and 24 weeks. Scalp and serum dihydrotestosterone levels decreased, and testosterone levels increased, in a dose-dependent fashion with dutasteride. Dutasteride increases scalp hair growth in men with male pattern hair loss. Type 1 and type 2 5alpha-reductase may be important in the pathogenesis and treatment of male pattern hair loss.


Dutasteride versus finasteride
Which medication works better for prostate related urinary retention?

Dutasteride vs finasteride: assessment of differences in acute urinary retention rates and surgical risk outcomes in an elderly population aged > or =65 years.
Am J Manag Care. 2008; Fenter TC, Davis EA, Shah MB, Lin PJ. University of Mississippi, Corporate Medical Advisor Blue Cross & Blue Shield of Mississippi, Jackson, MS, USA.
To determine comparative differences on rates of acute urinary retention and prostate-related surgeries among patients aged > or =65 years treated with dutasteride or finasteride. For this retrospective analysis, medical/pharmacy claims data from July 1, 2003, to June 30, 2006, were analyzed for enlarged prostate patients aged > or =65 years treated with 5-alpha reductase inhibitors (5ARIs) regardless of alpha-blocker use. A total of 5090 patients met selection criteria. After 1 year of 5ARI therapy, the acute urinary retention rate was lower for dutasteride (12%) when compared with finasteride (14.7%). Risks for prostate-related surgeries were also lower among dutasteride-treated patients (3.9% vs 5.1%, respectively). Important therapeutic outcome differences exist between dutasteride and finasteride. Patients treated with dutasteride were significantly less likely to experience acute urinary retention and prostate-related surgeries than finasteride patients.


Q. I sent you, under separate email, a “Live Science” article regarding a study that indicates that men with low testosterone die sooner. I am an “over 50” male with an enlarged prostate and relatively high PSA reading which has proven to be non-cancerous. I am taking dutasteride which has apparently shrunk my prostate to a reasonable size and the symptoms of frequent urination and difficulty in starting urination have gone away. The side effects seem to be a decreased semen production, but my sex drive is still there (not like when I was 25 though). If the article regarding low testosterone is correct, and if my assumption about dutasteride is correct, that it lowers testosterone levels, could dutasteride possibly shorten my life span?
     A. As far as we know, dutasteride blocks the conversion of testosterone to DHT, rather than decreasing testosterone levels. The long term health consequences of regular dutasteride use, and reduction of DHT levels, are not known. Just to be on the safe side, it is best to use dutasteride in as low a dosage as possible and perhaps taking occasional breaks from use. This has to be done in agreement with your prescribing doctor.


Q.  have a quick question concerning dutas. I am experiencing some hair loss now for a few years. Still have a full head of hair but it is definitely starting to thin. About a month ago I ordered Dr. Reddys dutas and started to take 5 mg a day of dutas. Its been about 4 weeks and it seems like I am shedding a lot of hair then before I started the drug. Is this normal and for your opinion do you think it i should stop soon? I know nothing is proved but off the record does this drug improve hair loss at all? What have you heard or seen as you have done your research through the years? Please let me know if I am wasting my time with this drug.
   A. According to a website, "Dutas is Dutasteride and is a generic form of Avodart. Dutas is made by Dr Reddy's Laboratory in India. Dr. Reddy's Laboratories Ltd has launched Dutas for the treatment of enlarged prostate. Dr. Reddy's is the first company to launch this drug in India." We are not familiar with this version of dutasteride so we don't know if it is effective.