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What is cromolyn sodium?


Cromolyn sodium is part of the drug class known as mast cell stabilizers that is indicated to treat mastocytosis, bronchial asthma, allergic rhinitis, keratitis, keratoconjunctivitis, and specific allergic eye conditions such as vernal conjunctivitis.

Off-label, cromolyn sodium is used to treat food allergies and management of inflammatory bowel disease.

Cromolyn sodium can be used in children older than 2 years old.

How does cromolyn sodium work?

As cromolyn sodium is a mast cell stabilizer, its mechanism of action is to block the release of inflammatory mediators, such as histamines and leukotrienes. When your body is exposed to allergens that could create symptoms of an allergic reaction, cromolyn sodium stops the mast cell degranulation that normally would show up in anaphylaxis.

For treatment of mastocytosis, cromolyn sodium stops mast cells from releasing substances that cause the symptoms of itching, rash, stomach/abdominal pain, flushing, pruritus, and diarrhea. Cromolyn sodium is not an antihistamine or a corticosteroid medication.

What doses of cromolyn sodium are available?

Cromolyn sodium comes in four different dosage forms:

  • A 100mg/5mL oral concentrate

  • 5.2 mg/1 actuation nasal spray (Nasalcrom)

  • 4% (10mL) ophthalmic solution

  • 10 mg/1mL inhalation solution

How do you use cromolyn sodium?

Follow all directions given by your doctor, including prescribing information, FDA-approved product labeling, and Medication Guide. The use will change depending on which form of cromolyn sodium you use. If you are prescribed:

The oral concentrate:

  • Dilute the contents with a glass of water and stir as well as you can.

  • For systemic mastocytosis: take the mixture 30 minutes before meals and at bedtime.

  • For food allergies and inflammatory bowel disease: take the mixture 15-20 minutes before meals.

The nasal inhalation:

  • For allergic rhinitis: use one spray per nostril three to six times a day.

The eye drops:

  • For vernal conjunctivitis/keratitis/vernal keratoconjunctivitis: drop one to two drops in each eye four to six times daily, equally spaced throughout your day.

The nebulizer solution:

  • For asthma prophylaxis: take one vial (20 mg) via a nebulizer four times a day at regular intervals.

The metered-dose inhaler:

  • For asthma prophylaxis: take two oral inhalations (800 mcg/spray) four times a day at regular intervals.

For pediatric patients, the concentration of medicine and the number of times a day they take the medication will change. Speak to your doctor about what is best for you or your child.

What are the side effects of cromolyn sodium?

Adverse reactions will most likely change depending on which dosage form you receive. However, the most common side effects of cromolyn sodium in clinical trials compared to placebo include:

If you’re using the ophthalmic solution:

  • Burning of eyes upon application

  • Puffiness

  • Irritation

  • Eye dryness

If you’re using the oral solution:

  • Constipation

  • Vomiting

  • Photosensitivity

  • Angioedema

  • Urticaria

If you’re using the nasal spray or inhalation solution:

  • Nasal congestion

  • Nasal itching

  • Sneezing

  • Nosebleeds

  • Throat irritation and hoarseness

  • Esophagitis

  • Drowsiness, dizziness, bronchial irritation, pulmonary infiltrates, and cough

If you’re using cromolyn sodium to treat mastocytosis:

  • Headache

  • Pruritus

  • Diarrhea

  • Nausea

  • Myalgia

  • Abdominal pain

  • Rash

  • Irritability

Other (general) possible side effects:

  • Dyspepsia

  • Glossitis 

  • Constipation

  • Stomatitis

  • Vomiting

Rarely, cromolyn sodium may cause some serious side effects, including:

  • Allergic reactions

    • Contact your healthcare team immediately if you experience any symptoms of an allergic reaction.

  • Eye drops may cause eye damage when wearing soft contact lenses.

 Contact your healthcare professional for medical advice about any possible adverse effects you experience while taking cromolyn sodium. You can report your adverse effects to the FDA at 1-800-FDA-1088 or

Cromolyn sodium drug interactions

Cromolyn sodium does not have any noted severe interactions with other drugs. However, you should still inform your healthcare professional if you are taking any other prescription drugs, over-the-counter medications, vitamins, and supplements.

Cromolyn sodium precautions

You should be sure that your healthcare provider is aware of all your medical conditions, including if you have:

  • Liver/kidney disease or impairment.

    • Severe anaphylactic reactions have occurred; dosing changes of cromolyn sodium may be recommended based on your condition.

  • A known allergy to cromolyn sodium.

  • A pregnancy, plan to become pregnant, or are breastfeeding.

    • It is unknown whether cromolyn sodium passes through breast milk.

    • Speak to your doctor about potential dosage changes for both pregnancy and best practices for lactation.

Is there a generic available for cromolyn sodium?

Yes, there are generics available for cromolyn sodium. Possible brand names include Gastrocrom or Intal (no longer offered).

How do you store cromolyn sodium?

Cromolyn sodium should be stored at room temperature, away from light and children. Keep it in the foil package until it is ready to use. Do not use it if the solution if it has become solid, cloudy, discolored, or is expired.

Related medications

Alamast (pemirolast potassium)

Alocril (nedocromil sodium)

Alomide (lodoxamide tromethamine)

Tilade (nedocromil sodium)

Pataday (olopatadine)



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