| Erythematous | Characterized by sharp cut-offs at the patch test site. Seen with fragrance mix, carbamate mix. |
| Follicular | Follicular papules as opposed to micro vesicles. Seen with nickel, cobalt. |
| Pustular | More common in atopic individuals[1]. Can be seen with metal salts (eg, nickel). Occasionally can be seen with true allergic reactions. |
| Soap irritation | Glazed erythematous appearance. Seen when testing soaps and shampoos. |
| Bullous/necrotic | Seen with high concentrations of caustic materials including gasoline, kerosene. |
