Here are the answers to your questions in the order they were asked:
If its caused by hairball....how long following the vomit should my cat spit it out ?
Cats do not have to ever produce a hairball to be nauseated by it. If you see coughing with swallowing, this suggests that a hairball may be the cause of the symptoms. There are a few things you can do. 1) Start brushing him daily to remove extra fur so he does not ingest it, 2) begin using a hairball treatment like laxatone/catalax/petromalt, 3) change to a hairball prevention formula food. These together can all but eliminate the hairball concern. If you are seeing an increase in fur, shedding and subsequent symptoms of hairball production consider shaving him down to prevent ingestion of fur and the symptoms that follow. Brushing 1-2 times daily can also help greatly.
If its not an hairball what could it be?
If this is not due to hairballs, it may be due to asthma. Your vet should be able to determine if asthma is an issue with blood work and a chest x-ray. Many cats have changes on both and he's not too young to have either at 1 year of age.
If he didnt changed his behavior and doesnt seem to be more drowsy, it shouldnt be that bad ?
If he still feels well, this is a good sign. It means that whatever is causing the symptoms is likely not a major ordeal for him.
Should I wait before giving him DRONTAL Tabs considering that he just vomited?
Wait for all coughing/vomiting to stop for at least 24 hours.
Because you have witnessed vomiting, you can administer a dose of regular pepcid (famotidine) every 12-24 hours. You will want to give 0.5mg/pound of body weight (a 10# ***** would receive 5mg, a 5# ***** would receive 2.5mg, etc). For this, you can visit any human pharmacy and buy the OTC brand name Pepcid, or you can use the cheaper, off-brand “famotidine” that’s available. Either will be useful.
I cannot tell you precisely why you're seeing so many bubbles but it may have something to do with repeated swallowing and air being brought into the stomach. The famotidine mentioned above should help as well as the brushing, laxatone and food changes mentioned in the first paragraph of this reply.
I’ll be standing by if you have other questions. Let me know if I can help further.
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