Hello, and welcome.
I'm sorry Matilda has you worried because she's not eating as usual. Older cats are more prone to develop conditions like diabetes, thyroid, liver and kidney issues and this may adversely affect her appetite. The only way to find out if there is an underlying medical problem is to have her seen in person by a vet and have a routine senior blood panel, including a thyroid test. If it is too traumatizing for her to be taken to the vet, you can have a vet come to YOU. You can find a housecall or mobile vet that can see her in her own environment, where she will feel more comfortable and less stressed. Search for a vet who will come to you, HERE
If she has not had a bowel movement for the last 24-48 hrs., you could be correct, that she is constipated. She may have a large hairball which combined with some hard, dry stool and will not move out on it's own. You can treat this at home by doing ONE of the following:
--Give her a hairball gel/laxative, such as Laxatone or Petromalt which are brand names, but every pet supply store should carry them. Follow directions on the product, but I usually recommend giving 1-2 inches, two to three times a day. These products may not be effective alone, but you can also give 1 tBS of plain, canned pumpkin (NOT pie filling) mixed with a small amount of canned food, and in combination, this may work.
--You can give over the counter Miralax (for humans) at a dose of 1/8th to 1/4 tsp. once a day, until you see some soft stools.
--As a last resort, a Pediatric glycerin suppository can be given; here is more information:
Read the product label carefully and make sure you only use ones with glycerin, as the ones with phosphorus are toxic to cats.
Try to get her to drink more and this will help. Also, wet food is healthier and provides more moisture. Here is a great series of articles written by a feline vet, about the best way to feed our cats:
I hope all will be well with your Matilda!
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