Probably a combination. Winter heating systems suck the moisture out of the air and cold winds outside can be further drying. I think it is probably flaky dry skin instead of dandruff. When the skin is dry already, it can be more sensitive to chemicals in shampoos. I can recommend a product from Espree called Luxury Remoisturizer -- it is a fantastic conditioner and does what the name says. I love Minksheen shampoo and any of the Espree products -- they have a Hypoallergenic Coconut shampoo that is especially gentle and might help during the dry months. They also have a Silky Show Shampoo that is great too.
Using quality products and RINSING extra well can help a lot. If it is still a problem might want to consider adding some Omega 3 fatty acids -- fish oils. There are several products made specially for dogs. Also make sure you are using a premium food. |