If she's having trouble passing urine, then stop the Clomicalm and call your vet ASAP. She may be having a reaction to it or it may have nothing to do w/it at all but it sounds as though she's developing a bladder infection. That's very painful and she'll continue to strain until she passes blood if she does have a bladder infection. Don't put off calling your vet. Time is of the essence.
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