It is difficult to know what pet meds are best for an animal with allergies and the nature of the problem can be hard to diagnose.
That is according to Donna Spector, an internal medicine specialist based in Illinois, US, who said that allergies are a “head-banger”.
She said: "They are frustrating for vets, they’re frustrating for clients and the dogs and cats itch like crazy so we know it is frustrating for them.
"Allergies are very challenging to diagnose accurately because it's a diagnosis of exclusion. It takes a lot of money and a lot of time. It takes a very dedicated owner."
The main types of allergy in pets come through fleas, food, contact with other animals and through airborne particles.
Ms Spector noted that most pet allergies cause scratching, but other symptoms can be rashes, open sores, watery eyes, ear infections, runny noses, vomiting, diarrhoea and hair discolouration between the toes.
Dogs Trust recently warned owners about the danger chocolate poses to dogs. They urged owners to make sure chocolate is out of reach of dogs ahead of Easter.