Using a Rescue Medication for Allergies or Asthma

Rescue medication is a medicine intended to relieve your symptoms immediately. Rescue medications are most often used for severe allergies, for asthma, or for migraines, and they're also known by the terms quick-acting medication and fast-acting medication.

These types of medication can save your life if you've been accidentally exposed to an allergen or if you're having a bad asthma attack. They also can stop a migraine in its tracks. But it's never a good idea to rely on them solely to protect you.

There are several different types of rescue medications, each of which has a specific purpose and use.

woman with inhaler
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Epinephrine for Allergic Reactions

Epinephrine, which is used to stop severe allergic reactions (anaphylaxis) that are potentially life-threatening, may be the best-known rescue medication.

It's used in the form of an injection (commonly referred to as an EpiPen, which is one brand name of the medication) that's administered as soon as possible when the reaction begins. It can treat allergic food reactions, reactions to insect stings or bites, adverse reactions to medications and even reactions resulting from latex allergy.

Epinephrine works quickly — within a few seconds to a minute of the injection. Epinephrine is a vasoconstrictor of most blood vessels, which counteracts the vasodilation effects of histamine. It is also a vasodilator of the blood vessels supplying the heart, which can help the heart pump more effectively. In addition, epinephrine stabilizes mast cell membranes and can stop the progression of an allergic reaction. However, its effects wear off quickly, usually within 10 to 15 minutes. So if you've used epinephrine as a rescue medication for your allergic reaction, you'll still need to seek immediate medical help.

Asthma Rescue Medications Stop Attacks

When you have asthma, your treatment goal should be to prevent asthma attacks. But since that's not always possible, asthma rescue medications can stop an attack quickly.

These medications, known as bronchodilators (dilators for your bronchi, or airways), help to open up your constricted airways, enabling you to breathe more easily. Many people with asthma carry one of these medications with them at all times in order to halt an asthma attack.

There are several brands of inhaled asthma rescue medications available by prescription.

Migraine Rescue Medications

A migraine headache is another condition where rescue medications should be kept on hand. Migraines can be severe and disabling, but prompt treatment with certain over-the-counter or prescription drugs can stop an attack.

There are a variety of different migraine rescue medications available, starting with basic over-the-counter pain relievers such as ibuprofen or acetaminophen. Some types of over-the-counter anti-headache drugs contain caffeine in addition to a pain reliever.

The most common prescription migraine rescue medications are triptans, which can be administered in pills, shots, suppositories or through inhalers. Triptans work by narrowing the blood vessels in your brain.

As a last resort, opioids or butalbital, a barbiturate, can be used as migraine rescue medicines. If your migraine pain is severe enough for you to visit the emergency room, the physicians there may treat you with one of these drugs to stop your migraine attack.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  • American Academy of Neurology. Choosing a Treatment for a Severe Migraine Relief fact sheet.
  • U.S. Library of Medicine. Asthma Quick-Relief Drugs fact sheet. 
  • U.S. Library of Medicine. Epinephrine Injection fact sheet. 

By Victoria Groce
Victoria Groce is a medical writer living with celiac disease who specializes in writing about dietary management of food allergies.