It's important to protect yourself from the harmful ultraviolet rays of the sun. Higher levels of exposure over the past 20 years have lead to a spike in the number of skin cancer cases reported recently, and the problem doesn't show any signs of slowing down. There is an easy fix: All you have to do is wear sunscreen. Unfortunately, for a small minority of the population, allergies can make that difficult.

There are two different types of sunscreen allergies that we know of. They are contact allergies and photoallergies. Put simply, contact allergies will cause a reaction as a result of application. That means anywhere you put sunscreen, you're going to have an allergic reaction, usually in the form of a rash. With photoallergies, however, you won't have an allergic reaction until you actually go outside in the sun. Sunlight reacts with chemicals in the sunscreen and your body to cause an allergic reaction [source: McCoy].

So how do you tell the two apart? It's not always easy, but a simple patch test can be the answer [source: Bassett]. A patch test involves putting a small patch of sunscreen on your body somewhere, often on the underside of your arm or your back. This is done in a controlled environment away from UV rays. If you're allergic, your body will react, but only in the small section where the patch was applied. If there is no initial reaction to the sunscreen, the patch can be placed under a UV light to see if the allergy is a photoallergy.

Patch testing can also be used to find out if a certain ingredient in the sunscreen you're using is causing your allergic reaction. If that's the case, all you have to do is find a sunscreen without that particular ingredient. If all else fails, you can also try using a physical sunscreen. These sunscreens often contain zinc oxide or titanium dioxide. Instead of absorbing UV rays, these chemical compounds reflect them, giving you a literal shield against the sun [source: McCoy].

Don't get burned by your allergies: It's important to wear sunscreen. If you're allergic, you should work with a dermatologist or another qualified physician to find an alternate form of sunblock.

Read on to get more information about sunscreen allergies.