You can buy pillow covers...usually white with zippers for removal.....remove just the pillow cover and wash it each week. As for deodorizing a pillow...if the weather was sunny..put it out in the sun. Otherwise, put it in your dryer and fluff/deordorize it that way.
Fabreeze for fabric.
As fast solution for lighter odors, the smelly pillow and fabric softener sheets can be be placed within the dryer. For best results, place at least 4-6 fabric softening sheets in within the dryer and run on the lightest setting for 20-30 minutes. This solution only works with synthetic and is not recommended for feather pillows.
As another solution for minor odors, baking soda can be sprinkle within the pillow case. To perform this solution, measure a quarter cup f baking soda and lightly sprinkle the ingredients into the pillow case on both sides. Proceed to shut the opening of the pillow cases and give it a good shake to evenly disperse the deodorizing powder through the inside of the pillow. Performing this task once a week should have a freshening effect of the underlying pillow.
This solution works by applying active enzymes that eat through much of the odorous organics embedded within your pillow. Begin this solution by removing the pillowcase and proceeding to spray down the pillow with enzyme cleaning spray from all directions. Finish by taking the pillow outside and hanging it within direct sunlight until it is completely dried.
Buy a new one. They are not that expensive.
I am with Pat on this one. Much healthier than breathing in chemicals from various "deodorizers" - if you just want a momentary refresh, a light spritz of rubbing alcohol will do too.
Put in the dryer with dryer sheets and a damp wash cloth with a little fabric softener on it