There are many diseases and conditions that can cause itch. Some of the most common include:
- Kidney disease
- Iron-deficiency anemia
- Thyroid disorders
- Cancer, such as leukemia or lymphoma
- Neurological disorders, such as multiple sclerosis or spinal cord injury
- Skin conditions such as eczema, psoriasis, and scabies
- Allergic reactions, such as hives or contact dermatitis