| Reaction | |
|---|
| Abrasion (2) | |
| Abscess (46) | |
| Acantholysis (1) | |
| Acanthosis nigricans (19) | |
| Acne keloid (5) | |
| Acne vulgaris ("acne") (1) | |
| Acneiform eruption / acneiform dermatitis (233) | |
| Acneiform papular (1) | |
| Acneiform pustular (1) | |
| Acral desquamation (1) | |
| Acral erythema (23) | |
| Acral necrosis (4) | |
| Acral purpura (2) | |
| Acral sclerosis (2) | |
| Acrodermatitis enteropathica (1) | |
| Actinic granuloma (1) | |
| Actinic keratoses (18) | |
| Acute febrile neutrophilic dermatosis (Sweet's syndrome) (67) | |
| Acute generalized exanthematous pustulosis (AGEP) (166) | |
| Allergic granulomatous angiitis (Churg–Strauss syndrome) (42) | |
| Allergic skin reactions (1) | |
| Anaphylactoid reactions / anaphylaxis (447) | |
| Anetoderma (2) | |
| Angioedema (390) | |
| Angiofibromatosis (1) | |
| Angiokeratoma (1) | |
| Angioma (2) | |
| Anhidrosis (2) | |
| Anticonvulsant hypersensitivity syndrome (15) | |
| Aplasia cutis congenita (2) | |
| Atopic dermatitis (10) | |
| Atrophie blanche (1) | |
| Atrophy (20) | |
