Can You Take Dutasteride And Finasteride Together?

Hair loss can be quite concerning, hence the unending search for a lasting solution. Luckily, a lot of research has been done to discover ways of reversing male pattern baldness. One such way is the use of over-the-counter or prescription medications like minoxidil and finasteride. 

Studies have also been done to check how safe and effective dutasteride could be in the treatment of hair loss. In this article, the pharmacist will discuss if it’s okay to take dutasteride and finasteride together for hair loss treatment or benign prostatic hyperplasia (BPH) in men.

What to Know about Finasteride and Dutasteride

Both dutasteride and finasteride are prescription-only medications belonging to a class of drugs called 5-alpha reductase inhibitors. They both work by blocking the conversion of testosterone to dihydrotestosterone (DHT) in the body, though the extent to which each drug does this varies [1]. 

Dihydrotestosterone has been proven to be responsible for the enlargement of the prostate in men, thereby causing the disease condition referred to as benign prostatic hyperplasia (BPH). 

It is also responsible for the miniaturization (shrinkage) of hair follicles, giving rise to thinner and weaker hair strands that eventually stop growing. This results in male pattern hair loss or what is also referred to as androgenetic alopecia [2].

Dutasteride and Finasteride prevent DHT production by inhibiting an enzyme called 5-alpha reductase. This enzyme is responsible for converting testosterone to dihydrotestosterone (DHT), a more potent male sex hormone. 

5-alpha reductase enzymes exist in two major forms identified as type I and type II.

Dutasteride works by blocking the action of both type I and type II 5-alpha reductase, leading to a 99% reduction in the amount of DHT present in the blood. Finasteride only blocks type II 5-alpha reductase, producing about 70% reduction in serum DHT level [1,3].

Oral Finasteride has been approved by the FDA for the treatment of male pattern baldness. It is available as an oral tablet under the brand name Propecia and is taken at a dose of 1 mg daily. Topical finasteride is also being used as a compounded medication but it is not approved by the FDA yet.

Dutasteride on the other hand has not been approved by the FDA for the treatment of hair loss in men or women. If used for this purpose, it is only off-label.

Can You Take Dutasteride And Finasteride Together?

It is not recommended to take both dutasteride and finasteride together as they both belong to the same class of drugs and also work the same way.

Combining these two drugs can put you at a heightened risk of experiencing side effects such as low sex drive, low volume of ejaculate, inability to get or maintain an erection, and also male breast enlargement (gynecomastia).

Dutasteride is only approved by the FDA for the treatment of BPH. A condition whereby the prostate enlarges, narrowing or blocking the tube through which urine passes to be voided. It causes symptoms such as: 

• Difficulty initiating a urine stream
• Frequent urination
• Urgency to urinate
• Weak urine stream
• Straining to urinate
• Dribbling after urination
• Incomplete bladder emptying, etc.

However, there have been studies on the potential use of dutasteride in the treatment of androgenetic alopecia. One study evaluated the efficacy, safety, and tolerability of 0.5 mg Dutasteride and placebo (a pill that does not contain any active drug) in male patients with male pattern hair loss [4]. 

The study was conducted over 6 months and the result showed that dutasteride was significantly more effective in the treatment of hair loss than placebo. It produced a significant amount of hair regrowth than the inactive pill (placebo). Dutasteride was also well tolerated in these patients.

In another study to assess the superiority of dutasteride over finasteride in hair regrowth and reversal of male pattern hair loss. Male patients with hair loss were divided into two groups. One group was treated with dutasteride while the other was treated with finasteride [5]. 

After 6 months, it was observed that the men treated with dutasteride had higher levels of hair regrowth than the group of men who took finasteride. This showed that dutasteride is more effective than finasteride in treating androgenetic alopecia. However, their side effect profiles were not any different, as the subjects were majorly facing sexual dysfunctions.

What Research Says About Combining Dutasteride With Finasteride

A 2012 case study found that combining low-dose dutasteride with ongoing finasteride treatment may boost hair regrowth in some men with androgenetic alopecia [6]. 

The study followed a 47-year-old male who had taken finasteride 1mg daily for 4 years to treat his hair loss. Although initially effective, the benefits of finasteride eroded after year 2 resulting in decreased hair density.

At this point, the subject was given a low 0.5mg per week dose of dutasteride in addition to the finasteride. After consistent combined treatment with both medications, the patient experienced a dramatic increase in hair density and growth. 

This suggests that dual treatment with both finasteride and dutasteride can improve hair regrowth in patients with androgenetic alopecia.

However, given the risks of heightened side effects with combined treatment, such off-label use should only be considered under medical supervision after careful analysis of potential benefits vs risks.

More research is still required with larger samples to fully confirm if combined low-dose dutasteride and finasteride therapy can bolster hair regrowth without compromising safety.

Final Thoughts

It is not advisable to take both dutasteride and finasteride together as doing so can increase your chances of experiencing side effects. Both drugs work almost the same way and are both effective in their approved indications for use. Do not self-medicate on any of these drugs without your doctor’s advice.

References

1. Salisbury BH, Tadi P. 5-Alpha-Reductase Inhibitors. [Updated 2023 Apr 14]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. 
2. Ho CH, Sood T, Zito PM. Androgenetic Alopecia. [Updated 2022 Oct 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. 
3. Zito PM, Bistas KG, Syed K. Finasteride. [Updated 2022 Aug 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. 
4. Hee Chul Eun, Oh Sang Kwon, Je Ho Yeon, Hyo Seung Shin, Byung Yoon Kim, Byung In Ro, Han Kyong Cho, Woo Young Sim, Bark Lynn Lew, Won-Soo Lee, Hwa Young Park, Seung Phil Hong, Jae Hong Ji. Efficacy, safety, and tolerability of dutasteride 0.5 mg once daily in male patients with male pattern hair loss: A randomized, double-blind, placebo-controlled, phase III study. Journal of the American Academy of Dermatology. Volume 63, Issue 2. 2010. Pages 252-258. ISSN 0190-9622.
5. Shanshanwal SJ, Dhurat RS. Superiority of dutasteride over finasteride in hair regrowth and reversal of miniaturization in men with androgenetic alopecia: A randomized controlled open-label, evaluator-blinded study. Indian J Dermatol Venereol Leprol 2017;83:47-54
6. Boyapati, A. and Sinclair, R. (2013), Combination therapy with finasteride and low-dose dutasteride in the treatment of androgenetic alopecia. Australasian Journal of Dermatology, 54: 49-51.