### Seborrheic Dermatitis vs. Psoriasis: How to Tell the Difference Both seborrheic dermatitis and psoriasis can cause red, scaly, and inflamed patches on your skin, making it difficult to distinguish between the two. Here's a simple guide to help you understand these conditions better. #### Seborrheic Dermatitis - **Appearance**: Patches may look whitish-yellow, red, or brown and tend to feel greasy or oily. - **Common Areas**: Scalp, oily parts of the face (like around the nose, ears, and eyebrows), upper chest, and back. - **Symptoms**: Itchiness, red or inflamed skin, and flaking. - **Triggers**: The exact cause is unclear, but it may involve factors like oily skin and certain yeast on the skin. - **Management**: Often managed with milder treatments compared to psoriasis. #### Psoriasis - **Appearance**: Starts as rough, red, scaly skin and grows into thick, usually silver-colored scales. - **Common Areas**: Scalp, torso, limbs, hands, and feet. - **Symptoms**: Itchiness, pain, and thick scales with more defined edges. It can also affect nails, causing them to become thicker and develop pits or ridges. - **Triggers**: Likely a combination of genetic factors and environmental triggers like infections, skin injuries, smoking, drinking, and stress. - **Management**: Often requires stronger medications. About one-third of people with psoriasis may develop psoriatic arthritis, leading to stiff and swollen joints. #### Similarities - Both conditions are lifelong and can take an emotional toll, especially when patches are noticeable. - Neither condition is contagious, but both can run in families. - Both can flare up due to triggers like weather or stress. #### Diagnosis - Doctors will examine your skin and scalp and may take a small skin sample to check under a microscope. - Newer microscopes can show differences in the shapes of the scales, helping to distinguish between the two conditions. If you have a persistent or worsening rash, consult your doctor for an accurate diagnosis and appropriate treatment. While the conditions are similar, treatments that work for one may not be effective for the other, especially in severe cases of psoriasis.