What to Know About Cromolyn Sodium

Table of Contents
View All
Table of Contents

Cromolyn sodium prevents and suppresses the over-active inflammatory process that contributes to allergy symptoms. It is a mast cell stabilizer and inhibits the release of histamine and immune proteins.

There are several formulations of cromolyn sodium used for various indications:

  • Cromolyn sodium for the treatment of allergies is available as an over-the-counter (OTC) nasal spray under the brand name NasalCrom.
  • A prescription ophthalmic solution—Crolom, Cromoptic, and Opticrom—is used for treating certain inflammatory eye conditions.
  • A prescription oral liquid form, Gastrocrom, is used for treating systemic mastocytosis, an inflammatory condition.
  • A prescription nebulizer solution is used for the treatment of acute asthma.

This medication is sometimes prescribed off-label for treating inflammatory conditions. Research is ongoing regarding its potential effectiveness for inflammatory conditions.

The prescription inhaler, Intal, which had previously been prescribed for the prevention of asthma symptoms has been discontinued.

This article will describe the uses, side effects, and precautions for the OTC nasal spray form of cromolyn sodium.

Nebulizer treatment

Getty Images/yulkapopkova


Cromolyn sodium is indicated for the treatment of allergies for adults and children over age 2. This medication is used to prevent and relieve nasal symptoms of hay fever and other nasal allergies.

The symptoms that it is used to treat are:

  • Runny nose
  • Itchy nose
  • Sneezing
  • Stuffy nose

Before Taking

If you have had an allergic reaction associated with cromolyn sodium, it is recommended that you don't use it or that you use it with caution according to your healthcare provider's instructions.

Talk to your healthcare provider about all medications, supplements, and vitamins that you currently take. While some drugs pose minor interaction risks, others may outright contraindicate use or prompt careful consideration as to whether the pros of treatment outweigh the cons in your case.

Precautions and Contraindications

This medication may pose a risk for children under age 2, pregnant mothers, and babies of mothers who are nursing.

You should not use this treatment if you have severe heart disease or arrhythmia (irregular heart rhythm).


If you have nasal allergy symptoms, you should follow your healthcare provider's instructions regarding a regular dosing regimen and as-needed preventative treatments, as appropriate.

Drug Form mg/Dose How to Take
NasalCrom Inhaler 5.2 mg per metered spray One spray in each nostril three to four times a day; max. six times a day if needed

The effect is expected to last for approximately one to two hours.

Cromolyn sodium should not be regularly used for longer than 12 weeks when used for allergies. Follow your prescriber's instructions.


If you have kidney disease or liver disease, your healthcare provider will recommend that you use a lower than recommended dose of cromolyn sodium. The reduction in dose will be based on the severity of your liver or kidney disease. The more impaired your liver or kidney function, the lower your recommended dose of cromolyn sodium.

How to Take and Store

It is important that you learn how to use the nasal spray correctly. You might consider taking your first dose when you are at your healthcare provider's office to ensure you are using it the right way. Children should only use the nasal spray under supervision.

Cromolyn sodium should be stored away from light at room temperature (between 68 and 77 degrees F).

Discard any remaining expired medication based on your pharmacist's instructions, or take it to your pharmacy for proper disposal.

Side Effects

While using cromolyn sodium is generally safe, there is a risk of a range of side effects.


Cromolyn sodium causes a number of mild side effects. You might experience them right when you start using the drug, or they can develop after you've used the treatment for months. Be sure to tell your healthcare provider if these effects are very bothersome for you.

Common side effects include:

  • Bad taste in your mouth
  • Cough
  • Itching
  • Sore throat
  • Headache
  • Sneezing or stuffy nose


Serious side effects are rare with cromolyn sodium, but they can occur and may include:

Be sure to contact your healthcare provider or seek urgent medical attention if you begin to experience serious side effects. Don't wait to see if a problem subsides on its own.

Warnings and Interactions

Using cromolyn sodium when you are currently experiencing asthma symptoms may make your asthma symptoms worse.

If you have had asthma for over 10 years, you might have used other forms of inhaled cromolyn sodium. Cromolyn sodium had been available under the brand name Intal as an asthma inhaler and a nebulizer solution.

The manufacturer stopped making Intal due to regulations regarding the safety of three chlorofluorocarbon (CFC), a material that was commonly used in many asthma inhalers as a propellant.

Cromolyn sodium is considered safe, but the formulations that used CFCs to help with the inhalation process are not permitted due to environmental concerns.

Cromolyn sodium is not known to have any drug interactions.

A Word From Verywell

Cromolyn sodium is an inhaled mast cell stabilizer used for treating allergy symptoms and for several other conditions for children and adults aged 2 and older. It is considered safe, with minimal warnings and side effects. Cromolyn sodium is no longer considered effective for preventing asthma symptoms.

If you have frequent nasal allergy symptoms that are interfering with your day-to-day life, talk with a healthcare provider about whether you need allergy testing or further interventions.

5 Sources
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.
  1. Puzzovio PG, Brüggemann TR, Pahima H, Mankuta D, Levy BD, Levi-Schaffer F. Cromolyn Sodium differentially regulates human mast cell and mouse leukocyte responses to control allergic inflammation. Pharmacol Res. 2022 Apr;178:106172. doi:10.1016/j.phrs.2022.106172

  2. Lieberman JA, Zhang J, Whitworth J, Cavender C. A randomized, double-blinded, placebo-controlled study of the use of viscous oral cromolyn sodium for the treatment of eosinophilic esophagitis. Ann Allergy Asthma Immunol. 2018 May;120(5):527-531. doi:10.1016/j.anai.2018.03.006

  3. Prescribers' Digital Reference. Cromolyn sodium drug summary.

  4. Asthma and Allergy Foundation of America. Cromolyn sodium.

  5. Food and Drug Administration. Intal inhaler label.

By Pat Bass, MD
Dr. Bass is a board-certified internist, pediatrician, and a Fellow of the American Academy of Pediatrics and the American College of Physicians.