Search our A to Z of Skin to find out more about common skin conditions and problems, their symptoms, causes and how they are diagnosed and treated. You can search by both common and medical names, or by medicine or treatment name.

Both common and medical names have been included to help your search, as well as the names of medications and treatments. There are also a number of cosmetic topics which explain the latest treatments for cosmetic concerns related to the skin. Our thanks go to the many College dermatologists have contributed to the information on this site.

The information provided in the A-Z of Skin is a general guide only and does not replace individual medical advice. Please speak to your doctor for advice about your situation. The ACD is not liable for any consequences arising from relying on this information.

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  • Hand foot and mouth disease

    Hand foot and mouth disease is a common contagious viral illness that spreads from person to person.

  • Hansen’s disease

    Hansen’s disease also known as Leprosy, is a chronic bacterial infection caused by the organism Mycobacterium leprae. It primarily affects the skin and the nerves. It may also affect mucous membranes (such as the nose) as well as eyes and testicles.

  • Heat rash

    Heat rash also known as miliaria, is a group of skin conditions that arise from blockage of sweat ducts.

  • Herpes gestationis

    Herpes gestationis also known as Pemphigoid gestationis (PG) is a relatively rare pregnancy dermatosis characterised by blisters.

  • Herpes Labialis

    Herpes labialis, also known as “cold sores”, is a common blistering viral infection of the lip or around the mouth.

  • Hidradenitis Suppurativa

    Hidradenitis suppurativa is a condition affecting apocrine sweat glands that are located mostly under the arms and in the groin and genital area. These glands become blocked and inflamed, and then swollen and painful.

  • Hirsutism

    The term Hirsutism refers to excessive hair production in both males and females. However, medically it is used to define increased hair growth in women. Hirsutism affects 5-10% of women.

  • Hives

    Hives is a skin condition also known as Urticaria.  It produces an itchy rash that tends to come and go and can last for a variable period of time. The condition can be acute (lasting less than 6 weeks) or chronic (lasting longer than 6 weeks). Most cases of urticaria have no known cause.

  • Hori’s Naevus

    Also known as ... Acquired Naevus of Ota-like Macules (ABNOM) and Naevus Fusco-caeruleus Zygomaticus. Horis naevus presents as benign (harmless) blue-grey to grey-brown patchy and spotty pigmentation on the prominence of the cheeks. The condition usually appears in adulthood. It is most common in middle-aged Asian women. 

  • Hormonal acne

    Hormonal acne also known as adult acne, is acne that continues past the ages of 18 to 20 or starts in the early 20s in individuals who may not have had a previous problem with acne.

  • Hot Comb Alopecia

    Hot comb alopecia also known as Central centrifugal cicatricial alopecia (CCCA) is a chronic and progressive type of scarring alopecia that results in permanent hair loss. CCCA most commonly starts in the centre of the scalp and, without treatment, expands over time causing an irreversible area of baldness. It is most commonly seen in middle-aged African women.

  • Human papillomavirus

    Human papillomavirus also known as warts, are abnormal growths of the skin and mucosa caused by an infection with the human papillomavirus (HPV).

  • Hutchinson’s melanotic freckle

    Hutchinson's melanotic freckle also known as lentigo maligna, is an early form of melanoma. In lentigo maligna the cancer cells are confined to the upper layer of the skin (epidermis).

  • Hyperhidrosis

    Hyperhidrosis is the name given to excessive or uncontrollable sweating.