- Can Botox reduce chronic hair shedding? Whether Botox reduces chronic shedding is unknown: one very small 2022 trial in telogen effluvium had no placebo arm, and the blood-flow theory is unproven. Scalp Botox for hair loss is off-label, and all botulinum toxin products carry an FDA boxed warning.
- How does cetirizine reduce inflammation linked to hair loss? Cetirizine is proposed to lower prostaglandin D2 and raise prostaglandin E2 around hair follicles; three small trials of a compounded 1% topical report modest increases in hair density and shaft thickness, with minoxidil doing better head-to-head. Topical cetirizine is off-label and unapproved for hair loss, and the evidence is too thin to call it effective or safe.
Mild corticosteroid used on the skin and scalp
Weak form of estrogen applied to the scalp
JAK inhibitor pill, an immune-system drug
Red-light devices, such as caps, combs and helmets, used on the scalp
Popular 5-alpha reductase inhibitor that lowers DHT, taken as a pill or used topically