I use the regular and scented lysol bottles...they all seem to work the same. I just like different smells sometimes LOL
First, I don't spray their head around the eyes with the Lysol, I wet a rag and rub around their heads. But I do use spray bottles on my horses with water to cool them and bathing them so they are desensitized to one. I think all horses should be desensitized to everything you could possibly think of to desensitize them to.
For desensitizing to a spray bottle I would have them in a halter and on a lead rope. Lay the lead rope over your left arm if you are spraying right handed and hold the spray bottle up around their head/eyes/ears. First, you might get a response of pulling back...not wanting it around their head but do not let up and keep it there until the horse relaxes. The second the horse relaxes retreat the bottle from around their head and pat/rub/give praise to them. Then try that same step again. Once the horse relaxes with the bottle being near their head start spraying. You probably will encounter resistance again but keep spraying and do not stop until the horse relaxes. The instant the horse relaxes retreat from spraying and give praise/rub/scratch/good boy/etc.....Keep doing this excersise until you get them to be completly relaxed while getting a spray. It is very important to try and give the very instant the relax praise. That tells them it is OK and they have given you the right answer. Make it uncomfortable for them to give you the wrong answer such as resisiting by continuing to spray.
You can try keeping them from being head shy from all things by tying a plastic bag to their halter and letting them go in the pasture/field/wherever they hang out. They make kick, run, buck at first but they will soon learn to accept it and not pay it a lick of attention. That will help alot for a head shy horse.
Hope this helps ~ PM me if you need any info...