Coughing in hamster is usually one of the first signs that there is a problem in [upper respiratory problems since they are prone to this. There are many causes of coughing in hamsters and coughing itself should not be cause for alarm but it is important that you determine what is the cause of this in order to make sure that your hamster stays healthy.

These are the causes of hamster's cough:

1. Allergies is one of the common causes of coughing in hamsters. Hamsters can develop allergies to their bedding, breathing in dust generated by pine shavings which can cause them to inhale particulate matter into their lungs causing them to cough. If you notice runny nose, watery eyes and sneezing present, then it is most likely that allergies is the cause of this. Take your hamster to a vet for him to be examined and determine what is the source of allergy.

2. Colds from humans can be transmitted to hamster and vice versa. If he looks sluggish and lethargic that usual, is coughing, sneezing and sniffling, this may be due to colds. Be sure to give him plenty of fresh water and fresh bedding. Feed him a piece of fresh fruit for the next few days to keep him hydrated. If the symptoms persist bring him to a veterinarian.

3. Flu is also possible, like colds hamsters can get this from human. The symptoms of the flu in hamsters are the same to those of a cold which include coughing, sneezing and sniffling. Fever is also present and hamster appears lethargic and listless and hot to the touch.
Give him fresh water and provide plenty of comfortable bedding and time to recover. Avoid handling him excessively for a few days. If you are concerned about the symptoms that he exhibits contact the vet immediately for this can be a sign of serious condition.

Have you been sick recently? Like humans, a hamster can catch a cold or even have the flu. I guess you would have to consult a pro to see what is really up.