A variety of other conditions may cause itching. The most common ones are:
- Infections with bacteria, yeasts or fungi
- Systemic diseases such as hormonal imbalance or liver disease
- Immune-mediated problems
- Allergies and hypersensitivities to airborne particles, food or by direct contact
To investigate the cause of the itching, the vet will normally conduct a full clinical examination and may well examine samples of skin or hair for signs of parasites and infectious agents. Blood tests may be needed to check for underlying problems and to screen for allergens. Where allergens are suspected, further investigation may be needed to determine the cause. This may involve diet trials using a special hypoallergenic diet, blood tests, or intradermal skin tests with a specialist veterinary dermatologist. Sometimes the underlying cause of the itching cannot be determined, even after carrying out a full investigation. In these cases, symptomatic treatment to control the itching may be needed.