Labored breathing is usually a symptom of parasites in the gill area as the fish is struggling to receive oxygen.
You didn't mention how long you've had the betta but note that the average life span of bettas is around 2 years. They're generally put up for sale when they are one year old.
So if you've had the betta for 1 year it would be considered advanced in age.
Bettas as they get older become highly suceptible to diseases despite receiving proper care.
What I suggest you do is start off by doing a partial water change. If the fish is in a bowl change all of the water using dechlorinated water that is the same temperature as the old water. If the fish is in a tank, change 1/2 the water.
Once the water change has been done add some aquarium salt at a ratio of 1 tablespoon per every 2.5 gallons/10 litres of water. If the water temperature is not in the range of 78f-80f/26c-27c degrees it would be advisable to adjust until it is within this range.
After all of the above has been done begin to treat the fish with a medicine called
Parasite Clear, click on upcoming link for a view of the product,
http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+4615+4620+4756&pcatid=4756 which can be found at most major pet stores.
Follow the directions on the product label for dosage instructions.
The fish's chances of recovery are dependant on how advanced the illness is and the fish's age.
Good luck and please let me know if you have any questions.
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OVER 20 YEARS EXPERIENCE W/TROPICAL FISH---BREEDING, MAINTAINING, CURING