Oral Minoxidil Side Effects: The Real Numbers From 1,404 Patients
Oral minoxidil side effects from 1,404 patients: hypertrichosis 15%, lightheadedness 1.7%, fluid 1.3%, 1.7% quit. Dose, heart risk, and the Loniten label.
Philippe Boissard
Philippe Boissard, M.Sc., is a hair loss researcher and author. He breaks down the science of androgenetic alopecia and the treatments men actually weigh up, working from the primary literature rather than marketing claims. New here? Start with his guide to how hair loss actually works.
Why Minoxidil Doesn't Work for Everyone: The SULT1A1 Enzyme Explained
Minoxidil is a prodrug activated by the scalp enzyme SULT1A1. The 1990 mechanism study, the enzyme test's accuracy, and what to do if you are a non-responder.
Scalp DHT vs Blood DHT: How Much Finasteride and Dutasteride Really Block
Finasteride cuts blood DHT by 70% but scalp DHT by far less. The biopsy studies behind the gap, what dutasteride adds, and why scalp DHT is what counts.
Hard Water and Hair Loss: Where the Evidence Actually Stops
Hard water measurably weakens the hair fibre. Whether it causes hair loss is a separate question, and the honest answer is that nobody has ever studied it.
Does Wearing a Hat Cause Hair Loss?
Two identical-twin studies measured hat wearing against hair loss and found hats on the protective side. What causes baldness, and when headwear does harm.
Thyroid, Hashimoto’s and Hair Loss: What the Evidence Supports
Thyroid disease causes hair loss and explains far fewer cases than people assume. The mechanism, the base rate, and how to tell it apart from pattern loss.
Alopecia Areata: What Actually Works in 2026
The JAK inhibitors approved for severe alopecia areata, their real response rates, what happens when you stop, and how strong the older treatments really are.
Dandruff, Seborrheic Dermatitis and Hair Loss: What Is Actually Linked
Is dandruff causing your hair loss? The real association, the Malassezia mechanism, and what medicated shampoo does to shedding, density and hair diameter.
Anabolic Steroids and Hair Loss: Why Finasteride Often Cannot Help
Why finasteride cannot touch most anabolic steroids, which compounds bypass the enzyme entirely, and what the evidence says about losing hair on cycle.
Minoxidil for Beard Growth: What the Trials Actually Show
What the two randomised trials of minoxidil for beard growth found, why it fails in most men, how long the shed lasts, and the microneedling evidence gap.