The short answer: It is not recommended.
The long answer: Peanut butter is a spread made from grounded, dry-roasted peanuts. Store-bought peanut butter is known for being high in protein and fat, but on the downside, it is also packed with salt, sugar, and additives that are harmful for your pet. Though peanut butter is not included on the ASPCA’s list of people foods toxic to cats, it does not have any nutritional value for them. Therefore, it is not advisable to feed it to your pet.
Similar to dog owners, some cat owners hide medication in peanut butter. However, this must be done by using raw, unadulterated peanut butter. It should be free from additives and the artificial sweetener called xylitol, which may also affect your cat. As a reminder, using peanut butter to hide medicine should be done sparingly. Feeding her too much peanut butter may cause vomiting, diarrhea, or even cause obstruction in your cat’s mouth or airway. Long-term effects include obesity and diabetes.
What to do if your cat accidentally eats peanut butter: Check the nutrition facts label of your store-bought peanut butter. If it includes harmful ingredients for your cat, call your veterinarian immediately. Observe her for any signs of abnormal behaviour such as vomiting, diarrhea, and salivation.
In summary: Though peanut butter is not considered toxic for cats, it is best not to feed it to your pet. She’s better off eating specially formulated cat treats or homemade treats that contain the nutritional value she needs.