Cats can only eat certain types of capsicum.
Capsicum is described by Wikipedia as “a genus of flowering plants in the nightshade family Solanaceae.” The plant bears fruits such as hot chili peppers (jalapeño, peperoncini, and peperoncino, to name a few) and mild bell peppers (which are simply called capsicum in Australia). These are sold fresh, pickled, or dried and turned into powder form.
In terms of eating capsicum, cats belong to the same boat as dogs that cannot consume certain kinds of capsicum. This is because the chemical capsaicin found in spicy varieties not only leaves a burning sensation in your pet’s mouth, it can also cause diarrhea and vomiting. Some cats may even experience nausea, indigestion, stomach pain, dehydration, excess salivation, runny nose, and/or teary eyes.
However, peppers that do not produce heat can be given to your cat once in a while. These include edible sweet peppers in red, yellow, green, and orange colours. These capsicums can be given occasionally and in moderation, as a treat or added to her meals. They can be eaten raw or lightly cooked without any oil or other ingredients such as salt, onions, and garlic (all lethal for cats!). Make sure to limit the peppers included in her daily diet, since she doesn’t actually need them to thrive.
What to do if your cat accidentally eats spicy capsicum: Contact your veterinarian immediately. Find out how much capsicum your cat has eaten, and report your observations and findings to the vet. Depending on how much your cat has consumed, she may experience gastrointestinal and digestive issues. These include but are not limited to upset stomach, diarrhea, and vomiting.
In summary: Capsicums may be eaten by your pet cat as long as they are the non-spicy variety, and are prepared correctly. Raw sweet peppers that are rich in carbohydrates and vitamins C and B6 may be given to her in small amounts. On the other hand, hot peppers should be avoided at all costs since eating them may lead to unwanted health complications.