A natural incapacitating effect of pepper spray is the swelling of the linings of the nose and throat. This will make breathing difficult for anyone, but for those with preexisting respiratory problems, such as asthma, it can lead to more severe problems.
Chemical burns, blistering and sores can result from naturally and artificially derived pepper spray. This reaction is more likely in individuals who are allergic to oleoresin capsicum, or who have had allergic reaction to peppers in the past.
Pepper spray is usually sprayed at the face, particularly the eyes. It typically causes tearing, redness, pain and, in some cases, swelling and chemical burns around the eye area.
Some people experience temporary blindness after being exposed to pepper spray. This typically lasts no more than 30 minutes to an hour, but it can be frightening. There have been no studies related to the long-term effects of temporary blindness resulting from exposure to pepper spray.
Although it is rare, death can result from exposure to pepper spray. Deaths related to pepper spray are usually due to advanced age, preexisting heart conditions, or preexisting respiratory problems. Those with severe allergies to oleoresin capsicum may experience shock or become unable to breathe once exposed to pepper spray, leading to suffocation and death.