Types of ‘bugs’ that cause skin disease


There are 4 types of things that would cause skin disease in a dog.  All conditions (other than truly auto immune conditions) can be completely reversed. Please note however that most severe itching and skin loss causes secondary bacterial and fungal infections too so the disease may not be only one – but the cause has to be addressed for the dog to get better.

  1. Bugs that are called ectoparasites (literally the things that live on the outside i.e. in the hair). These include fleas & ticks.

    • Flea infestations can cause severe allergic reaction so fleas are bad news.

    • Hair loss comes from severe and repeated itching with the paws and teeth.

    • Ticks can cause tick fever – which if untreated will be fatal so ticks are very bad news.

    • Treatment includes application of medication (topical)

    • Common examples are:  Ticks, Fleas

  2. Bugs that are called endoparasites. These are mites that live under the skin/ hair follicle. These cause severe itching and

    • Hair loss comes from the fair follicles being eaten away and from severe and repeated itching with the paws and teeth.

    • Treatment includes medicating the dog  AND  application of medication

    • Common examples are:  Sarcoptic Mange, Demodectic Mange

  3. (Auto) Immune conditions – when immunity of a dog is compromised and that has caused an allergy and/or a secondary infection to develop. Allergic dermatitis and ‘hot spots’ / wet eczema are these types of disorders.

    • Treatment includes addressing the cause of the lower immunity/ high stress, topical treatment and medication

    • Common examples are:  Wet Eczema, Allergic Dermatitis, Lick Granuloma, Immune Disorders

  4. Bacterial and fungal growth – these include ring worms etc. Most of the time  fungal infection if untreated will have a bacterial infection as well and vice versa. Some dogs with ‘leathery’ black smooth skin is due to ‘mature’ fungal growth.

    • Treatment includes medicating the dog  AND  application of medication

    • Common examples are: Fungal/ Yeast infections, Ringworm, Seborrhea


There are over 160 different skin disorders of dogs, mange is only one of them!


It is common for most people see all severe hair loss as ‘mange’. However dogs suffer from many types of skin diseases all causing hair loss and only one/few of them are ‘mange’. Treatment differs for different diseases so please try and identify what does the dog have to give it treatment. Identification and treatment SHOULD be done by a vet (or you can send us a request). Looking at dog does not always give an idea of what is wrong. Your vet should do a skin scrape use a microscope.