I would purchase Laxatone. It is an effective and inexpensive laxative as well as hairball remover. If his stomach seems upset, brew some peppermint tea and offer him a tablespoon (wait 'til it cools) You may also utilize mineral oil in his food and I would recommend adding a bit of canned pumpkin or bran to each of his meals if the constipation continues to be a problem. If after the use of the laxative, the fella still hasn't pooped, then he may be impacted (and dehydrated) and needs to see a vet for the removal of the feces.
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