Renal (Kidney) Failure
Whether or not your cat has diabetes, kidney problems are very common.

Weak Back Legs (Neuropathy)
Sometimes occurs when BG levels are highly uncontrolled, this condition causes weakness in the rear legs.

Somogyi Effect
After hypoglycemia from an insulin overdose, the body sometimes responds with abnormally high, uncontrollable BG levels.

Hyperthyroidism
A metabolic disorder which can cause many of the same conditions concurrent with feline diabetes, such as PU/PD, weight loss, lethargy/hyperactivity, more.

Hepatic Lipidosis
Also known as "fatty liver disease", often caused when an obese cat stops eating for one week or more, starts vomiting and losing weight.

Pancreatitis
Uncommon, but obese cats are at risk for damage to the pancreas. Abnormal bleeding, vomiting, anorexia are common signs.

Cushing's Disease
A common name for a rare disease in cats, hyperadrenocorticism.