Head shaking in dogs is usually due to ear infection.Your dog might be having inner or middle ear infection. This infection can cause vestibular disease. Vestibular system is responsible for maintaining balance. Middle ear polyps, head trauma, toxic reactions to some drugs like metronidazole etc can also cause vestibular disease. Diagnosis of your dog's illness requires
- Medical history
- Complete physical examination
- Ear examination
- Neurological examination
- Complete blood count test
- X-rays skull
- CT or MRI scan
- Spinal tap test
- Serum biochemistry