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Cromolyn

Brand names: NasalCrom, Nasal Allergy Control, Nasalcrom Child

What is cromolyn used for?

  • Cromolyn is used to ease allergy signs.
  • It is used to prevent nose stuffiness.

Before taking cromolyn, tell your doctor:

  • If you are allergic to cromolyn; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.

This medicine may interact with other drugs or health problems.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take cromolyn with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take cromolyn?

  • Tell all of your health care providers that you take cromolyn. This includes your doctors, nurses, pharmacists, and dentists.
  • If you have had any recent nose surgery, injury, ulcers, or sores, talk with your doctor.
  • It may take a few weeks to see the full effect.
  • Do not use cromolyn to treat a sinus infection, asthma, or cold symptoms.
  • This medicine may cause harm if swallowed. If cromolyn is swallowed, call a doctor or poison control center right away.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using cromolyn while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is cromolyn best taken?

Use cromolyn as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Keep taking cromolyn to prevent the allergy. Once signs start, cromolyn will not help.
  • Do not take cromolyn by mouth. Use in your nose only. Keep out of your mouth and eyes (may burn).
  • Shake well before use.
  • Blow your nose before use.
  • Close 1 nostril.
  • When using, tilt your head forward a little.
  • Put nose spray tube into other nostril.
  • While breathing in through the nose, press down once to release spray.
  • Breathe out from your mouth.
  • Spray up the nose only. Do not spray onto the wall joining the two nostrils.

What do I do if I miss a dose?

  • Use a missed dose as soon as you think about it.
  • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
  • Do not use 2 doses at the same time or extra doses.

What are the side effects of cromolyn that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Shortness of breath.
  • Bad nose irritation.

What are some other side effects of cromolyn?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Nose irritation.
  • Sneezing.
  • Stinging.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out cromolyn?

  • Store at room temperature.
  • Protect from light.
  • Store in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

Consumer information use and disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about cromolyn, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take cromolyn or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to cromolyn. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated April 5, 2023.