New kitten: If you have just obtained your kitten it may meow excessively for the first few days. Leaving it’s mother and siblings and moving into a new house with new owners is a huge change to your kitten.
Loss of a companion: Cats are sensitive creatures and form close bonds with their owners and other pets in the household. If there are changes to the family dynamics, such as a separation, or the loss of an animal, this may cause your cat to meow more than usual.
Moving house: Again, this is a big change for your cat and may result in it becoming more vocal.
Attention seeking: Excessive vocalisation may be a result of your cat is feeling lonely or not receiving enough attention from his owner.
Outside influences: A neighbourhood cat coming onto your cat’s territory.
Old age: Some old cats may meow excessively. This usually happens when they begin to lose their cognitive functions.
Medical problems: If your cat is sick or in pain it may result in excessive vocalisation.
Nocturnal behaviour: Cats by nature are nocturnal, and may meow more during the night.
Diet: There are several diet-related possibilities. A sudden switch in your cat’s food can cause diarrhea. Food allergies and food intolerances may also cause diarrhea. Cows milk or dairy products being a common cause as many cats are lactose intolerant. Other foods may also cause a food intolerance in your cat.
Ingestion of poisons (rat poison, aspirin). It is possible for cats to either directly consume rat poison or to indirectly become poisoned by killing and/or eating a rodent who has ingested rat poison itself