Thank you for your question. Constipated dogs often appear to be very uncomfortable, and may strain whilst trying to pass faeces. They may whine, have difficulty walking, repeatedly try to pass faeces with little success, and may also refuse to eat.
There are several things you can try at home to help if your dog is constipated. If he is still accepting food then you can try feeding him a high-quality canned dog food with a high fibre content (this has the additional benefit of having a high water content). You can also supplement your dog's food with fibre, such as bran, or try feeding pure canned pumpkin which also has a high fibre content - many dogs find this very tasty and are often happy to eat it despite being constipated.
Another method you can try is mixing a small amount of olive oil or castor oil into your dog's food, which should act as a stimulant and make it easier for him to pass faeces. Adding too much olive/castor oil, however, can result in diarrhoea, so it is important to only use small amounts until he starts to pass faeces, and to monitor him for signs of diarrhoea. Always ensure that your dog has access to fresh drinking water. Olive/castor oil is the only type of laxative I would recommend using - do not give him any human medications.
If your dog refuses to eat any of these foods over the next day, or if these methods do not help with your dog's constipation within one or two days, then I recommend that you take him to your vet for an examination. It is important that your dog's constipation is treated, and your vet will be able to examine him thoroughly and prescribe medications that specifically help with constipation.
In the future, adding fibre to your dog's everyday diet (such as bran or a commercial fibre supplement suitable for dogs), may help to prevent him from becoming constipated again.
Hope this helps and best wishes,
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