Generic Name: Cromolyn Brand Name(s): Generics only. No brands available.


What is cromolyn used for?

Cromolyn oral:

It is commonly used treat the symptoms of a condition called mastocytosis, which can cause diarrhea, nausea, vomiting, headaches, stomach pain, itchy skin, and flushing (warmth or redness under the skin).

Cromolyn inhalation:

It is used to help prevent the symptoms of asthma, bronchospasm caused by exercise, or allergies. These symptoms include shortness of breath, cough, wheezing, or a tight feeling in the chest.

Cromolyn eye drop:

It used to treat certain allergic eye conditions (vernal keratoconjunctivitis, vernal conjunctivitis, vernal keratitis). It prevents itching of the eyes that can occur with these conditions.

Cromolyn may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should I take cromolyn?

Cromolyn capsule:

Take this medication by mouth 15 to 20 minutes before meals.

It is advisable not to not crush, break, or chew the capsule. Swallow cromolyn whole with a glass of water.

Cromolyn inhalation with a nebulizer:

  • Break open the ampule and empty the medicine into the chamber of the nebulizer. Attach the mouthpiece or face mask to the drug chamber. Then, attach the drug chamber to the compressor.
  • Sit upright in a comfortable position. Place the mouthpiece into your mouth or put the face mask on, covering your nose and mouth. Turn on the compressor.
  • Breathe in slowly and evenly until you have inhaled all of the medicine. The treatment is complete when no more mist is formed by the nebulizer and the drug chamber is empty.
  • Clean the nebulizer after each use. Follow the cleaning directions that came with your nebulizer.

Cromolyn with a metered-dose inhaler:

  • Uncap the mouthpiece of the inhaler and shake the inhaler gently.
  • Breathe out fully. Put the mouthpiece into your mouth and close your lips. Do not block the mouthpiece with your tongue. Tilt your head back and breathe in slowly while pushing down on the top of the canister. Take the inhaler out of your mouth and hold your breath for several seconds, then breathe out slowly.
  • Clean your inhaler twice a week by removing the canister and rinsing the mouthpiece under warm running water. Allow the parts to dry before putting the inhaler back together. Never place the medicine canister in water.

Cromolyn eye drops:

  • To apply eye drops, wash your hands first.
  • To avoid contamination, do not touch the dropper tip or let it touch your eye or any other surface.
  • It is best to avoid wearing contact lenses while using this medication.
  • Tilt your head back, look upward, and pull down the lower eyelid to make a pouch. Hold the dropper directly over the eye and place 1 drop into the pouch. Look downward and gently close your eyes for 1 to 2 minutes. Place one finger at the corner of the eye near the nose and apply gentle pressure. This will prevent the medication from draining away from the eye. Try not to blink and do not rub the eye. Repeat these steps if your dose is for more than 1 drop and for the other eye if so directed.
  • Do not rinse the dropper. Replace the dropper cap tightly after each use.

Ask your health care provider any questions you may have about how to use cromolyn.

How do I store cromolyn?

Cromolyn is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store cromolyn in the bathroom or the freezer. There may be different brands of cromolyn that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush cromolyn down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.


Precautions & warnings

What should I know before using cromolyn?

Consult with your doctor or pharmacist, if:

  • You are pregnant or breastfeeding. This is because, while you are expecting or feeding a baby, you should only take medicines on the recommendation of a doctor.
  • You are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • You have allergy with any of active or inactive ingredients of cromolyn or other medications.
  • You have any other illnesses, disorders, or medical conditions.
  • You have any other types of allergies, such as to foods, dyes, preservatives, or animals.

Is it safe during pregnancy or breastfeeding?


There are no adequate studies in women for determining risk when using this medication during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking this medication. This medication is pregnancy risk category B, according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk
  • B=No risk in some studies
  • C=There may be some risk
  • D=Positive evidence of risk
  • X=Contraindicated
  • N=Unknown


Unknown if excreted in breast milk, use with caution.

Always consult your health care provider prior to using this medication if you are pregnant, breastfeeding.

Side effects

What side effects can occur from cromolyn?

Here are common side effects:

  • Nausea
  • Headache
  • Joint pain
  • Trouble sleeping
  • Allergic reaction such as rash, itching/swelling (especially of the face/tongue/throat)
  • Severe dizziness
  • Trouble breathing
  • Muscle weakness
  • Unusual tiredness
  • Swelling of the ankles/feet

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.



What drugs may interact with cromolyn?

Cromolyn may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs, and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with cromolyn?

Cromolyn may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with cromolyn?

Cromolyn may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have, especially:

  • Heart disease
  • A heart rhythm disorder
  • Coronary artery disease
  • Kidney disease
  • Liver disease



The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this medication.

What is the dose of cromolyn for an adult?

Cromolyn oral

  • Mastocytosis: 200 mg PO four times daily; 30 minutes prior to meals; may increase to 40 mg/kg/day if control of symptoms not seen within 2-3 weeks.
  • Food allergy & inflammatory bowel disease (off-label): 200 mg PO four times daily; may double dose if effect not satisfactory within 2-3 weeks; not to exceed 400 mg orally four times daily.

Cromolyn inhalation                

  • To prevent bronchial asthma attacks: given 4 times daily. If you are using cromolyn sodium inhalation to prevent asthma caused by exercise, air pollutants, or exposure to chemicals, use the medicine 10 to 15 minutes (but not more than 1 hour) before exercising or exposure.

Cromolyn eye drop:

Used in the affected eye(s), usually 4 times daily or as directed by your doctor. Treatment may be continued for as long as 3 months.

What is the dose of Cromolyn for a child?

Cromolyn oral

  • Mastocytosis:
  • <2 years: safety and efficacy not established.
  • 2-12 years: 100 mg PO four times daily; not to exceed 40 mg/kg/day; give 30 minutes before meal and bedtime.
  • >12 years: As in adults; 200 mg orally four times daily; 30 minutes prior to meals; may increase to <40 mg/kg/day if control of symptoms not seen within 2-3 weeks.
  • Food allergy & inflammatory bowel disease (off-label)
  • <2 years old: Not recommended.
  • 2-12 years: 100 mg four times daily initially; may double dose if effect not satisfactory within 2-3 weeks; not to exceed 40 mg/kg/day.
  • >12 years: 200 mg orally four times daily; may double dose if effect not satisfactory within 2-3 weeks; not to exceed 400 mg orally four times daily.

How is cromolyn available?

Cromolyn is available in the following dosage forms and strengths:

  • Cromolyn nebulizer/metered-dose inhale: 20mg/ml
  • Cromolyn capsule 100mg
  • Cromolyn eye drops 40 mg (4%)

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

It is also important to carry a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking with you in case of emergencies.

What should I do if I miss a dose?

If you miss a dose of cromolyn, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Review Date: December 29, 2016 | Last Modified: January 4, 2017

You might also like