Complex answer. Finasteride is FDA & TGA approved for hair loss, dutasteride is not. The flipside is that dutasteride is a more potent inhibitor of 5 alpha reductase. This results in more inhibition of DHT. Some papers have given the edge to dutasteride, but the outcomes are marginal at 5 years (controversial).

Most dermatologists will gravitate towards finasteride due the fact that more robust studies have been conducted over a longer period of time (however some will prescribe dutasteride because of the advantage in some papers).

In some cases, we prescribe both finasteride & dutasteride together, namely in a ‘pulsed’ manner. For example, finasteride Monday to Friday & dutasteride weekend, alternatively low dose finasteride 1mg daily with dutasteride one day a week. 

Yes, however this is off label. You will need to discuss this with your prescribing dermatologist. Large studies have shown that finasteride & dutasteride are highly effective in improving androgenetic alopecia in 68.9% & 65% of women respectively.

Another option is to use minoxidil 5% & finasteride 0.1%-0.25%. Though most studies show low to negligible serum levels of finasteride, the usual pregnancy precautions apply. Conventional management by specialists include the use of minoxidil orally at 1-2 mg per day, with other anti-androgens including cyproterone acetate & spironolactone.

A more conservate approach is to combine topicals with low level laser devices, thulium laser, as well as micro needling + platelet rich plasma. 

Finasteride can be prescribed in a lotion, with formulations typically ranging from 0.1 to 0.25 mg. Lotions have a much lower side effect profile. Most dermatologists will add topical minoxidil to this solution with concentrations ranging from 3 to 7%. This formulation is considered as the ideal solution for hair loss.

Another option is to use minoxidil 5-7% as a stand-alone solution. In some cases, we add retinoic acid to aid in absorption.

The most notorious side effect of these tablets is sexual dysfunction. The relative risk is thought to be 1.39 X the normal population. In the vast majority of cases, this is reversible upon discontinuation. There have been reports of permanent dysfunction. The risks of sexual dysfunction following topical lotions are much less than oral formulations. 

These side effects have also been reported with finasteride & dutasteride:

• Breast enlargement known as gynaecomastia. This is a rare side effect of both finasteride & dutasteride
• Depression/suicidal ideation
• Decreased sex drive that continued after stopping medication.
• Problems with ejaculation that continued after stopping the medication.
• Testicular pain & erection difficulties
• Male infertility.
• Finasteride & dutasteride are classed as teratogenic & not compatible with pregnancy & lactation. Prescriptions in females are off-label and at the discretion of your dermatologist.

Finasteride & dutasteride can affect a blood test called PSA (prostate-specific antigen), which is used in screening for prostate cancer. An elevated PSA number might be a sign of the disease.  These drugs may decrease PSA levels. If you have a PSA test done, tell your healthcare provider you’re taking finasteride; they’ll need to evaluate any changes in your PSA levels. You should also tell your healthcare provider if you haven’t been taking finasteride as prescribed because this may affect PSA test results too.

The most effective alternative to oral medication is topical finasteride or dutasteride, preferably with topical 5% minoxidil. This is a compounded formulation prescribed by a medical dermatologist. Other effective options include-

• Minoxidil: Liquid or foam, 5% concentration applied to the scalp twice a day to slow or stop the progression of male pattern baldness and thinning hair. It must be used continuously. If you discontinue minoxidil, new hair growth may reverse, and hair loss will continue. Minoxidil can also be taken as an oral medication, 1-2 mg daily.
• PRP or platelet rich plasma.  In this treatment, a patient’s blood is drawn and placed into a centrifuge to extract plasma that is injected into the scalp. Growth factors & chemokines found in platelets can stimulate hair growth. A study published in the International Journal of Molecular Sciences found that PRP treatment increased the number of hairs and overall hair density (Gentile, 2017).
• Low-level laser light therapy (LLLT) in the 600 to 1000 nm wavelength  is an effective method to treat hair loss. They emit a constant red LED light that is believed to reduce inflammation and increase blood flow to the hair follicles.
• Thulium laser is another effective non-pharmacological method to revive hair counts. The 1927 nm laser stimulates follicles. This is best used with topicals or medical therapy.
• Hair Transplant Surgery: In FUE or follicular unit extraction, donor hairs are removed from the sides and back of the scalp (areas which are more resistant to DHT) and implanted into areas of male pattern baldness.

Discuss treatment options with your medical dermatologist. Effective & early management is critical as this preserves your remaining hair follicles.  In most cases the diagnosis is straightforward, however in some cases hair microscopy & biopsies may be required.

Medical dermatologists can manage all forms of hair loss ranging from androgenic alopecia through to more unusual causes, including telogen effluvium, anagen effluvium, alopecia areata, lichen planopilaris, lupus, diffuse & chronic telogen effluvium as well as rare genetic disorders.

Disclaimer: I am a procedural dermatologist. I may be asked to provide input into challenging cases, namely to provide a diagnosis, however I do not get involved in medical management.

As a guide-

Topical minoxidil: about 50 cents a day

Topical compounded finasteride & minoxidil: about $2 per day

Oral finasteride: about 20 – 30 cents a day (Proscar 5mg break into half)

Oral dutasteride: about $2-2.40 a day

Minoxidil is cost effective. In fact, the price of this topical is only one fifth of the original price two decades ago as Regaine had the patent. Generic lotions are available from most pharmacies. Purchase a 3 to 6 month supply as this is more cost effective.

Finasteride can be bought as Propecia 1 mg or better still as Proscar 5 mg. The 5 mg can be broken down into quarter of half tablets with an average dose of 1.25 mg daily.