Could it be parasites or itch only?

Possibly — but straining changes the differential toward urinary emergency. Get checked.

Possibly — but straining changes the differential toward urinary emergency. Get checked.

Cat licking penis and straining

That combination is a reason to check the litter box carefully and call for emergency advice.

Scenario	Cat urinary blockage
Vet vs poison control vs ER	This is an ER veterinary emergency, not poison control. Blocked cats can become critically ill within hours. Call the clinic while you drive.

Treat repeated litter-box trips with little or no urine as an emergency in male cats especially
Note straining, crying, licking the penis, vomiting, or hiding
Do not give pain medications meant for humans
Call an ER or your veterinarian immediately and prepare to transport
Bring a urine sample only if it does not delay leaving

Licking looks like grooming. Pair it with litter visits and urine volume.

A damp bathroom rug with tiny spots can be the only urine produced.

Some cats suffer quietly. Rising lethargy is enough to leave.

Avoid baths and stress that delay transport.

This is general information, not a diagnosis. Contact your vet for anything urgent or unclear.

Could it be parasites or itch only?: Possibly — but straining changes the differential toward urinary emergency. Get checked.