Like the rest of the skin, the gums are susceptible to allergic reactions.
As the result of infiltration with inflammatory cells, the gums appear reddened. If irritation persists for a longer period of time, the base of the gums may brake open, erode, and bleed.
In most cases, inflammation is triggered by food allergies. Certain proteins or ingredients are known to cause allergic reactions of the gums.
Treatment of contact allergies is most effective if the underlying cause can be identified. A hypoallergenic diet is often successful. However, medication is necessary in severe cases. The dog may be returned to his usual diet after the gums have healed sufficiently.
If the dog is frequently chewing on plastic objects or containers, these should be removed as they might cause an irritation of the gums. Feeding your dog a homemade diet of rice or potatoes with chicken or horsemeat may show good results after a couple of weeks. If there is no improvement in the condition of the gums a vet should be consulted. Allergy testing can also help to identify the cause of irritation and help to design a suitable hypoallergenic diet.