Hi friend-
Straining in the litter box is indicative of a urinary tract infection or crystals in the urine. Fortunately, this is pretty easy to clear up with an oral antibiotic. I would also suggest giving her a drop of unsweetened cranberry juice once a day after her treatment is finished to help maintain a correct urinary ph level and help prevent this from happening again.
Please let me know if I can assist further.
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Lori McLaughlin
Your veterinarian should ALWAYS be consulted first and foremost when your pet's welfare is at stake.

