The reasons why cats keep shaking their heads:

1. Cat head shaking may be a normal physiological phenomenon and there are no other abnormalities.

2. The cat shaking its head may also mean that water or foreign objects have entered the cat’s ears, and the cat wants to shake its head to throw the foreign objects out.

3. Cat head shaking may also be caused by bacterial infection in the ear canal, causing itchiness of the ear canal.

Solutions to cats that keep shaking their heads:
1. If it is a normal physiological phenomenon, there is no need to worry too much. This is a normal behavior of cats.

2. If it is caused by the entry of foreign matter, you need to remove the foreign matter in the cat’s ears promptly and disinfect the cat’s ears to prevent infection.

3. If it is caused by ear canal infection, you need to use a special pet ear canal cleaner to disinfect and clean the cat's ear canal.