Ticks are parasitic insects that make a small wound in the dog's skin and drink the dog's blood. The tick drops off when it is engorged, or it may be removed using a pair of tweezers. In addition to being uncomfortable for the dog, ticks spread disease, so if you know that your dog has been bitten by a tick, keep an eye on the tick bite for the next few days to watch for signs of infection or illness.
Inspect and monitor the size of the tick bite. Ideally, the bite will stay the same size and start to shrink rapidly. If the bite does not shrink, but gets larger, it is a sign of infection.
Look at the skin around the bite. The dog's skin should be smooth and even in color. If you notice a red, raised area around the bite, it is a rash that indicates an infection.
Watch the dog's behavior. If the dog seems constantly tired and listless after a tick bite, particularly if it was not fatigued before the bite, its body may be fighting off an infection.
Watch the way the dog moves. Infections from tick bites may result in muscle pain that manifests as a limp or as a sensitivity to placing pressure on a certain area.
Spray the affected area with hydrocortisone spray, using the instructions on the spray bottle. Continue the spray program for a week, and if the dog does not recover, take it to the veterinarian for antibiotics.