A Shih Tzu (UK: /ˌʃiːˈtsuː/, US: /ˈʃiːˌtsuː/; Chinese: 西施犬; pinyin: Xī Shī quǎn literally 'Xi Shi dog', also spelled Shittsu) is a toy dog breed, weighing from 4 to 7.25 kilograms (9–16 lb) when fully grown. They may be a little temperamental with hyper or larger breeds, but generally, the Shih Tzu gets along well with other pets. They are generally well behaved and suitable for families. 6.2 Intervertebral disk disease. The coat color changes as the dog gets older.