Cromolyn (Oral)

Cromolyn is an oral medication used to treat asthma and mastocytosis as well as its symptoms.


People who suffer from a rare condition called mastocytosis may be treated with cromolyn or Gastrocrom. This medication prevents mast cells from releasing the substances that create symptoms such as diarrhea, vomiting, nausea, abdominal pain, itching, hives, and flushing. Cromolyn is available by prescription only. Before you begin a course of treatment with cromolyn, you should tell your doctor about any allergies you may have including food allergies. Cromolyn may also be used help control some forms of asthma in patients.

If you have kidney disease or liver disease, you may need to be monitored more closely during your treatment because the effects of cromolyn may be increased. This increase may allow for easier development of side effects. If you are on a low sodium diet, you should alert your healthcare provider because cromolyn also contains sodium. Take this medication with a full glass of water and refrain from mixing it with food, fruit juice, or milk. If you miss your dose of medication, take it as soon as you remember unless it is time for your next dose already. Do not take two doses of your medication at the same time because it could pose a risk to your health or create unpleasant side effects.

Condition treated

  • Mastocytosis
  • Asthma

Type of medicine

  • Mast cell stabilizer
  • Asthma treatment

Side effects

In addition to the intended effects, this drug may produce unwanted or serious side effects.

Rare side effects:

  • Hives

Developing hives is a result of an allergic reaction in most cases, and should be treated with immediate medical attention.

  • Difficulty swallowing

If you develop difficulty swallowing, you may be experiencing anaphylaxis and should seek emergency medical treatment.

  • Itching

Itching is rare, but a minor side effect. If this condition persists or worsens, or is accompanied by a rash, you should tell your doctor right away.

  • Tightness in chest

Tightness in your chest should be treated as a potentially life-threatening situation.

  • Swelling of the eyelids, face, or lips

Facial swelling is a sign of an allergic reaction that requires medical attention.

  • Shortness of breath

Shortness of breath may accompany facial swelling and a number of other signs of allergic reaction.

  • Wheezing

Wheezing may accompany shortness of breath.

  • Headache

Depending on the severity of your headache, you may want to seek professional medical advice.

  • Diarrhea

If you experience persistent diarrhea, you may have an intolerance to this medication, or you may have an underlying medical condition.

  • Abdominal pain

Abdominal pain should be treated as a serious side effect. Abdominal pain may also be caused by the condition you are trying to treat.

  • Nausea

If nausea is accompanied by other side effects you may be having an allergic reaction, or you may have an intolerance to cromolyn.

Frequency unknown:

  • Abdominal pain

Abdominal pain can be caused by your condition or may be a sign of intolerance.

  • Abnormal hepatic function test

Your doctor will discuss your options if you have an abnormal hepatic function test.

  • Constipation

If you experience constipation, you can ask about medication to help relieve this issue.

  • Dyspepsia

If you experience dyspepsia, or indigestion, you should ask what medication you can take to help eliminate this problem.

  • Flatulence

Some individuals may experience flatulence with cromolyn.

  • Stomatitis

If you notice an inflamed or sore mouth you may not tolerate this medication well.

  • Vomiting

Vomiting is a sign of intolerance or an overdose.

  • Throat irritation

Report any throat irritation to your healthcare provider because it may signal a developing condition.

  • Unpleasant taste

Unpleasant taste is a minor reaction that should disappear after the initial adjustment period.

  • Stomachache

A stomachache may be a sign of intolerance, or can be symptoms of your condition.

  • Swollen glands

You may experience swelling of the glands in some instances.

  • Dysphagia

Difficulty swallowing can signal anaphylaxis.

  • Oesophagospasm

Spasms in the esophagus should be treated as a severe reaction.

  • Tachycardia

If you notice a rapid heartbeat you should seek medical attention.

  • Flushing

Flushing may either be caused by your condition, or may be a sign of an intolerance to cromolyn.

  • Premature ventricular contractions

Report any issues with your heart to your doctor immediately.

  • Palpitations

Heart palpitations should be addressed by your healthcare provider.

  • Chest pain

Chest pain can signal a life-threatening emergency.

  • Fatigue

Fatigue is a mild side effect that may disappear after a few weeks.

  • Malaise

If malaise continues past the adjustment phase, you should ask about your other treatment options.

  • Tinnitus

Tinnitus is a mild, but persistent side effects. You may need to pursue a different course of treatment to alleviate this side effect.

  • Vertigo

Tell your doctor if you experience vertigo as a result of taking cromolyn.

  • Anxiety

Anxiety is not common, but can be treated with additional medication in some instances.

  • Depression

If you begin to experience depression, you should discuss treatment options with your healthcare provider.

  • Psychosis

If you experience psychosis, seek emergency medical treatment.

  • Hallucinations

Hallucinations are a severe side effect and require medical attention.

  • Insomnia

Insomnia can occur when taking cromolyn. Ask your healthcare provider about medications you can take to alleviate this side effect.

  • Behavior changes

You may wish to consult with your doctor about behavior changes, especially if they are severe.

  • Nervousness

If you experience nervousness while taking cromolyn, you may need to change treatments or ask for a dose adjustment.

  • Stiffness or weakness in the legs

If you experience weakness or stiffness in the legs, you may not tolerate this medication well.

  • Arthralgia

Some individuals taking cromolyn may experience pain in a joint. If the condition worsens you should seek the advice of your doctor.

  • Lupus erythematosus syndrome

The frequency of developing lupus as a result of taking this medication is not known. Lupus is a serious autoimmune disease that requires professional medical treatment.

  • Joint pain and swelling

You may experience swelling in conjunction with joint pain in some cases when you take cromolyn.

  • Polymyositis

You may experience muscle damage and swelling if you develop polymyositis as a result of taking this medication.

More common side effects:

These side effects are minor and will usually go away on their own after the initial adjustment period.

  • Coughing
  • Throat dryness or irritation


The normal adult dose used to treat systematic mastocytosis is 200 mg orally approximately 30 minutes before meals and before bedtime. It may take up to 2 to 3 weeks for the desired effects to be achieved. If necessary the dose may be raised after 2 to 3 weeks. The maximum recommended dose for adults who are treating mastocytosis is 40 mg per day.

The pediatric dose is recommended to begin at 100 mg for children ages 2 to 12. The medication should be taken half an hour before meals and bedtime. Children aged 13 years or older should begin their initial dose at 200 mg half an hour before meals and bed. The dose can be reduced to 40 mg per day after the therapeutic effect has been achieved after 2 to 3 weeks.


Medications known to interact with cromolyn

  • Rapid-acting inhaled insulin

Cromolyn is known to prevent proper absorption of insulin into the bloodstream.

  • Exubera

A rapid-acting inhaled insulin.

  • Afrezza

A rapid-acting inhaled insulin.

Disease interaction risk:

  • Renal disease

If you have renal disease, the use of cromolyn can cause medical complications. Tell your doctor about your renal dysfunction before beginning treatment, and follow the doctor's orders regarding testing while taking cromolyn.

  • Liver disease

An improper liver function can cause problems when taking this medication. If you notice any side effects you should alert your doctor immediately. Many doctors and healthcare providers will want to do regular testing to ensure your body is processing this drug correctly.


If you are allergic to cromolyn, you should tell your doctor and refrain from taking this medication. If you have liver or renal disease you should monitor your condition closely and inquire about potential dose adjustment. Do not stop taking this medication, or start taking this medication without the knowledge or consent of your doctor. If you add any medications to your daily routine, you should tell your doctor to help prevent the possibility of interaction and side effects. If you are pregnant or nursing, you should consult your healthcare provider before beginning treatment with cromolyn. Do not store this medication where children or pets can come into contact with it. If you begin to have severe side effects, or believe you are allergic to this medication, you should seek emergency medical treatment immediately. Do not flush this medication down the toilet and do not take it if it has expired.


Keep this medication in the original bottle and keep the cap locked. Do not store near heat, light, or humidity. Avoid storing other medications in the same container as cromolyn. Do not leave this prescription where children and animals have access to it. If you plan to travel, bring your medication in the original bottle with your name on it. Do not flush this drug down the toilet. Use your local community take-back program or follow the FDA's guidelines for proper medication disposal. If your medication expired, you should discard it and talk to your doctor about collecting a new prescription. If your medication becomes contaminated with other substances or moisture, you should not take it, but rather, replace it with a new prescription. Keep this drug stored at room temperature and avoid major temperature changes.


Cromolyn is a medication that is given to people to help them control the growth of mast cells in their body. Primarily it is used to treat mastocytosis in infants, children, and adults. The dose is based on the body weight and medical conditions related to the patient. The brand name for this medication is Gastrocrom. It is available by prescription only and should be taken as directed by your doctor. This drug helps relieve the symptoms of mastocytosis which is the overabundance of mast cells that cause a headache, flushing, itching, vomiting, diarrhea, nausea, pain in the abdomen, and hives. It works to prevent the cells from releasing the substance that is responsible for causing these debilitating symptoms.

If you have liver or kidney disease, it is important to closely monitor your condition and be aware that you may require a dose adjustment. Do not take more of this medication than your doctor prescribes. Do not stop taking this medication or change the dose without the consent of your doctor. Keep this medication out of the reach of children and pets. Do not store this drug near heat, light, or excessive humidity. If this medication expires, you should discuss getting a new prescription from your healthcare provider. If you must dispose of this medication use your local community take-back program. Do not flush this medicine down the toilet.

If you experience symptoms of an allergic reaction to this medication, you should seek emergency medical assistance. This should be the course of action for any serious side effects as well. Do not add any medications to your routine without checking with your doctor first. If you develop any new medical conditions while under treatment with this drug, you should inform your doctor.