Glossary of Terms

5-alpha reductase - the enzyme necessary to convert testosterone to dihydrotestosterone (DHT).

Alopecia - hair loss.

Alopecia areata - spot baldness.

Alopecia totalis - a condition that results in no hair on the scalp.

Alopecia universalis - a condition that results in no hair on any part of the body, this includes eyelashes, eyebrows, pubic hair and scalp hair.

Androgen - any steroid hormone that increases male characteristics.

Androgenetic alopecia - the medical name for male or female pattern baldness, the most common form of hair loss.

Biopsy - piece of tissue cut out for microscopic examination.

BPH - benign prostaic hyperplasia is a condition usually found in older men, when the prostate gland swells, restricting urine flow. It shares a common cause and cure with male pattern baldness.

DHT - the acronym for dihydrotestosterone. Classified as a “sex hormone”, it promotes hair growth on the face and upper pubis but has just the opposite effect on the scalp.

FDA - the US Food and Drug Administration. It is responsible for ensuring that foods are safe, wholesome and sanitary; that human and veterinary drugs, biological products, and medical devices are safe and effective; and that cosmetics and electronic products that emit radiation are safe.

Finasteride - an active substance and the generic name for Propecia and Proscar.

Follicle - a saclike structure just below the surface of the scalp. The sheath within which hair grows.

Follicular unit - natural groupings of hair that grow together as a group in the scalp and share the same blood supply.

Follicular unit extraction (FUE) - modification of the standard follicular unit transplantation where follicular units are removed individually from the donor area.

Follicular unit transplantation (FUT) - an advanced form of hair transplantation in which the surgeon extracts hair from a narrow strip of the back of the scalp in naturally occurring follicular units and grafts them to balding sections of the scalp.

FPB - the acronym for female pattern baldness, it is progressive thinning of hair throughout the entire head caused by genes, age and hormones.

Hair cloning - currently not available, but cloning hair may make it possible to secure an unlimited crop of donor hair for hair transplants.

HT - the acronym for hair transplantation.

MPB - male pattern baldness. This is the most common type of hair loss that is caused by hormones and affects the central and frontal area of the scalp and often results in a pronounced horseshoe pattern.

Miniaturisation - the destructive process by which DHT shrinks hair follicles, a key marker of androgenetic alopecia.

Minoxidil - an active substance and generic name for Rogaine and Regaine.

NW - the Norwood-Hamilton scale is a graphic scale for the classification of male pattern baldness.

OTC drugs - drugs that can be purchased without a prescription are called over the counter (OTC) drugs.

Placebo - a pill, topical application, or injection made to appear exactly like a normal medication, but without any of its active ingredients.

Propecia - the first FDA approved pill for hair loss. Propecia contains 1mg of finasteride, which inhibits the enzyme 5-alpha reductase type II that converts testosterone into DHT. This lowering of DHT in the body leads to a halting of hair loss and causes regrowth of hair in people suffering from male pattern baldness.

Proscar - a medication for treating an enlarged prostate (BPH) that contains 5mg of finasteride, the same ingredient that is in Propecia. Some men use Proscar instead of Propecia since it is cheaper when cut into five pieces.

Rogaine - the US brand name for minoxidil. Outside of the US it is usually marketed under the name Regain.

Telogen Effluvium - the second most common form of hair loss. A condition that causes an increased number of hairs to enter the resting phase.

Terminal Hair - normal pigmented hair that appears on the scalp, face, armpits, and pubic areas.

Vellus Hair - fine baby peach-fuzz hair that is not easily visible to the naked eye.

Vertex - the crown area of the scalp.