I am sorry Clausenfus is not feeling well.Since he is a male cat he should be seen today.
I do not want to alarm you but I am very concerned about your boy.These are very serious and can even be life threatening symptoms Any time a cat doesn't use his box he is either sick or in pain.
You should make a trip to the vet ASAP. - I think he has a urinary tract infection and is in danger of becoming blocked.
UTI's are serious in males because they are caused by sticky crystals in the bladder.At any time they can block the urethra.Since this is going on a while your boy is in great danger.Cats are very stoic animals so he may not cry out.
You can give him a half tsp of cranberry juice to lower the PH of his urine but he still needs to be seen for an antibiotic.
For the cough give him a drop of honey every 4 hours to sooth his throat.
If he becomes unable to urinate that is a MEDICAL EMERGENCY . His bladder could burst and he would have to be catheterized to save his life.
He most likely has a urinary tract infection.Brown urine can indicate a problem with the kidneys.Or dehydration.
If he gets dehydrated give him tuna water drained from the can.
Please let me know how he is doing .
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