Ketoconazole (KTZ) is a broad-spectrum azole antifungal that was licensed by the US Food and Drug Administration (FDA) in 1981 for the treatment of systemic fungal infections. When applied topically, ketoconazole, an imidazole broad-spectrum antifungal and steroid biosynthesis inhibitor, encourages hair growth. The mechanism involves lowering inflammation through antiinflammatory effects against T cells and Malassezia’s activity against skin bacteria (1).
Read our comprehensive guides on hairloss, their causes and solutions here first.
Is Ketoconazole effective for hair loss?
Yes, but not for all types of hairloss
Research and clinical studies have shown that ketoconazole is particularly helpful in treating androgenetic alopecia (AGA) due to its function in disrupting the dihydrotestosterone (DHT) pathway and due to its anti-inflammatory and anti-fungal effects. Androgenetic alopecia (AGA) is a genetically determined progressive hair-loss syndrome that is the most frequent cause of hair loss in males. Ketoconazole has been proved to be an effective treatment for AGA. In men aged 21–33, long-term usage of shampoos having 2% ketoconazole enhanced the density, size, and proportion of anagen follicles (2).
Increased levels of dihydrotestosterone (DHT) binding to hair follicle androgen receptors (AR) cause hair follicle shrinking, hair shaft diameter reduction, and anagen phase shortening, which is hypothesized to be the cause of androgenetic alopecia (3,4). In rat and human studies, KTZ inhibits 5α-reductase, lowering endogenous DHT synthesis and binding AR at high doses (5,6). KTZ’s antifungal, sebum-reducing, and direct anti-inflammatory effects via inhibition of 5- lipoxygenase may potentially help with AGA clinical improvement (7).
Ketoconazole Shampoo: Effect of Long-Term Use in Androgenic Alopecia.
The use of topical ketoconazole to treat androgenetic alopecia (AGA) has been studied. Treatment with 2 percent KTZ shampoo two to four times weekly for 39 male patients with Hamilton Grade III AGA over a 21-month period resulted in a progressive increase in pilary index (defined as hair shaft diameter in µm 1.5 cm (about 0.59 in)
from bulb obtained from computerized MOP Video plan Kontron image multiplied by percentage of hairs in anagen phase obtained from trichogram), while unmedicated shampoo resulted in a slow linear pilary index decrease (2).
Figure 1 – Ketoconazole shows significant improvement in hair growth over unmedicated groups, but the subject has to be predisposed to fungal scalp infections and is not effective for everyone (Pierard-Franchimont Et al).
Comparative Efficacy of Various Treatment Regimens For Androgenetic Alopecia In Men
Another six-month trial on 150 patients aged 18 to 65 years found that using 1% KTZ shampoo two to three times weekly significantly enhanced hair shaft diameter while having no effect on mean hair density (8). In a final study, 100 male patients with Hamilton Grades II to IV AGA were compared to oral finasteride 1 mg/day and 2% topical minoxidil alone vs
combination therapy of oral finasteride with 2% topical minoxidil and oral finasteride with 2% KTZ shampoo for a year. When compared to oral finasteride or topical minoxidil alone, oral finasteride with topical KTZ showed considerable clinical improvement (p=0.01), and was comparable combining oral finasteride and topical minoxidil (p=0.3) (9).
Figure 2 – Clinical photograph of a patient with AGA. (A) Before treatment, (B) After 1 year of treatment with oral finasteride +2% ketoconazole shampoo showing moderate improvement (2+) (Khandpur Et al).