If your cat receives too much insulin their blood glucose level can drop very low. This is called hypoglycemia (hypo = low; glycemia = glucose in the blood). Signs of hypoglycemia are:
- Weakness
- Disorientation, star-gazing, bumping into things, staggering/drunken walking
- Collapse
If the hypoglycemia is severe they can enter a coma or seizure so it is important to seek veterinary attention or advice immediately if you notice any symptoms.
Having glucose syrup or powder (available from most pharmacies) on hand is sensible and these or honey can be given to your cat to help increase their blood glucose levels while you seek veterinary attention.