Peanut allergies are related to your immune system. Instead of recognizing peanuts as a harmless and tasty food, your body thinks their proteins are dangerous. Since the cause for peanut allergies is a mistake programmed into your body, there isn't really a cure. Doctors aren't even sure why some people develop allergies and others don't. They do know that genetics plays a part, though. If other people in your family have allergies, there's a fair chance that you have them, too. Also, if you're allergic to one type of food, you are more likely to become allergic to other types of foods than someone with no allergies. Age also plays a role: Food allergies are most common in children, and kids often outgrow their allergies. However, a peanut allergy is one of the allergies that are hardest to outgrow. And even those who do outgrow peanut allergies might relapse later in life.
Unfortunately, there isn't even a treatment for peanut allergies. The best way to get around peanut allergies is to avoid coming in contact with peanuts. This means not eating peanuts, but it also means reading the ingredients lists on the labels of everything you plan to eat. Since peanuts are such a common allergen, manufacturers make your life easier by printing phrases like "may contain nuts" or "produced in a facility that also processes nuts" on the labels of foods that may have come in contact with peanuts.
The other step in managing peanut allergies is to always be prepared for a reaction. If your allergies are minor, that means carrying over-the-counter drugs with you to block the histamines that peanuts cause. However, if your peanut allergy is severe, you need to keep an epinephrine injection (or EpiPen) with you at all times. Epinephrine will halt an anaphylactic reaction until you can get medical attention.