Sodium Cromoglycate/Cromolyn

Sodium cromoglycate, also called cromolyn sodium or sodium cromoglicate, is a medicine used to help prevent allergy and asthma symptoms. It comes as a nebulizer solution, a nasal spray, eye drops, an oral liquid, and, in some countries, an inhaler.

What Is Sodium Cromoglycate (Cromolyn)?

Sodium cromoglycate and cromolyn sodium are two names for the same medicine. It helps stop the release of the chemicals that cause allergic reactions, and it is used to prevent symptoms rather than to relieve them once they begin.

Drug class: Mast cell stabilizer.

Approved and Common Prescribed Uses

Depending on the country, form, and label, sodium cromoglycate is used for:

• Asthma (inhaled or nebulized): regular (preventive) treatment to help reduce asthma symptoms and flare-ups.
• Exercise-induced bronchospasm: use shortly before exercise or exposure to a known trigger to help prevent airway tightening.
• Allergic rhinitis (nasal spray): prevention and relief of sneezing, runny nose, itching, and nasal congestion caused by seasonal or year-round allergies.
• Allergic conjunctivitis (eye drops): prevention and relief of itchy, red, watery eyes caused by allergies.
• Mastocytosis (oral liquid): management of symptoms such as stomach pain, diarrhea, flushing, and itching in people with this rare condition, where labeled.
• Other uses in some countries, as directed by a doctor.

Sodium cromoglycate is not a rescue medicine. It does not relieve a sudden asthma attack.

Available Formulations and Strengths

Formulation	Common Strengths	Main Use
Nebulizer solution	About 20 mg per 2 mL vial	Asthma
Metered-dose inhaler	About 1 mg or 5 mg per puff	Asthma, in some countries
Nasal spray	About 4% solution, or about 5.2 mg per spray	Allergic rhinitis
Eye drops	Commonly 2% or 4%	Allergic conjunctivitis
Oral concentrate (liquid)	About 100 mg per 5 mL	Mastocytosis, and other uses in some countries

Available products, strengths, and approved ages differ by country and brand. A prescriber or pharmacist can confirm what applies to a particular patient.

What Is the Recommended Dosage of Sodium Cromoglycate (Cromolyn)?

A licensed healthcare professional, or the product label for over-the-counter products, sets the dose. It depends on:

• The condition being treated and how severe it is.
• The form used: nebulized, nasal, eye, and oral products are each dosed differently.
• Age: children and adults often use different amounts, and approved ages vary by product. Some products are not approved for very young children.
• Body weight, which may be used for some oral doses in children.
• Liver and kidney function: people with severe liver or kidney disease may need lower doses and closer monitoring.
• Other medicines being used for the same condition.

Dosage Forms

• Nebulizer solution
• Inhaler, in some countries
• Nasal spray
• Eye drops
• Oral liquid

General Use Information

Sodium cromoglycate usually has to be used several times a day to work well, and it often needs regular use for one to several weeks before the full benefit appears. It is typically used on a schedule, not just when symptoms occur.

• Nebulizer solution: use only in a nebulizer machine, as directed, and do not swallow it.
• Nasal spray: blow your nose gently first, then use as directed.
• Eye drops: avoid touching the dropper tip to your eye or any surface.
• Oral liquid: may be mixed with water as directed, and taken before meals in some cases. Do not mix it with fruit juice, milk, or food unless the label says it is allowed.

For exercise prevention, use it shortly before activity, as directed. Follow your specialist’s instructions and the pharmacy label.

How Sodium Cromoglycate (Cromolyn) Works

In allergic conditions, cells called mast cells release chemicals, such as histamine, when they meet triggers like pollen, dust mites, pets, or exercise. These chemicals cause swelling, mucus, itching, and airway tightening.

Sodium cromoglycate helps stabilize the mast cells so they release fewer of these chemicals. This lowers the chance of symptoms when a trigger appears. Because it works by prevention, it does not give fast relief once symptoms have started.

Sodium cromoglycate helps manage allergy and asthma symptoms but does not cure them. It works best when used regularly as directed.

Is a Prescription Required to Buy Sodium Cromoglycate (Cromolyn) Online?

It depends on the form and the country.

• Nebulizer solution, inhalers, and oral liquid: These are available by prescription only in most countries.
• Nasal spray: In the United States and some other countries, certain nasal sprays are available without a prescription for allergy symptoms.
• Eye drops: In some countries, certain eye drops are sold without a prescription for allergic eye symptoms, while stronger products require one.

Check the label, and talk with a pharmacist or healthcare professional, especially for children or for long-term use.

Which Specialist Can Help?

• A pulmonologist (lung specialist) or allergist/immunologist often manages asthma and allergic conditions.
• An ear, nose, and throat (ENT) specialist may help with nasal and sinus conditions.
• An eye doctor (ophthalmologist or optometrist) may help with allergic eye symptoms.
• A gastroenterologist or allergist may be involved in mastocytosis or other oral uses.
• A pediatrician or primary care provider may also prescribe it and follow the patient over time.

Buying Safely

• Buy only from licensed pharmacies.
• Be wary of sites that sell prescription products without a prescription or at prices that seem too low. Such products may be counterfeit, expired, badly stored, or contain the wrong ingredients.
• Make sure the package is sealed, properly labeled, and has an expiration date. If anything looks odd, ask a pharmacist.

Side Effects of Sodium Cromoglycate (Cromolyn)

Many people tolerate sodium cromoglycate well, because very little of it is absorbed into the body, but side effects can occur. Not everyone will have them.

Common Side Effects

Nebulized or inhaled:

• Cough or throat irritation
• Wheezing or chest tightness right after use
• Unpleasant taste
• Nausea
• Dizziness or headache

Nasal spray:

• Sneezing
• Stinging, burning, or irritation in the nose
• Headache
• Unpleasant taste
• Nosebleeds, in some cases

Eye drops:

• Stinging or burning right after use
• Watery or red eyes
• Temporary blurred vision

Oral liquid:

• Headache
• Stomach pain, nausea, or diarrhea
• Skin itching or rash
• Tiredness or trouble sleeping

Serious Side Effects

These are uncommon but important:

• Breathing that suddenly gets worse right after a dose (bronchospasm)
• Allergic reactions: rash, hives, swelling of the face, lips, or tongue, or trouble breathing
• Inflammation of the lungs (eosinophilic pneumonia), reported rarely, shown by cough, fever, and shortness of breath that does not go away
• Severe skin reactions, reported rarely

When to Get Medical Help Right Away

Seek emergency care if there is:

• Severe trouble breathing, or breathing that worsens after using the medicine
• Swelling of the face, lips, tongue, or throat
• A severe skin rash or blistering

Contact a healthcare professional soon if symptoms are getting worse, if you have a cough or fever that does not go away, or if eye pain, vision changes, or swelling occur.

Drug Interactions

Sodium cromoglycate has few known interactions, since little of it enters the bloodstream. Give your specialist and pharmacist a full list of everything you use.

Prescription Medicine Categories

• Other asthma and allergy medicines, such as bronchodilators, steroids, antihistamines, and leukotriene medicines. Sodium cromoglycate is often used together with these, but the combination and any dose changes should be directed by your doctor.
• Steroid medicines, which may be lowered gradually by a doctor as asthma control improves. Do not stop or reduce steroids on your own.
• Other eye drops, where a healthcare professional may advise waiting several minutes between products.

Over-the-Counter (OTC) Medicines

• Allergy medicines, such as antihistamines or nasal decongestants, are often used with sodium cromoglycate, but check with a pharmacist before combining products.
• Other OTC nasal or eye products should be used only with a healthcare professional’s approval.

Supplements and Herbal Products

• Tell your healthcare professional about any supplement or herbal product you use.
• Some herbal products can affect allergies or breathing. Ask before using them.

Do not start, stop, or change any medicine or supplement without telling your healthcare professional.

Safety & Important Considerations

Not for Sudden Symptoms

Sodium cromoglycate does not treat a sudden asthma attack. Keep a fast-acting rescue inhaler on hand as directed, and get emergency help if breathing gets worse.

Needs Regular Use

Benefit may take days to weeks. Do not stop using it because you feel no effect right away, and do not stop it suddenly if you feel well, unless your doctor says to.

Do Not Stop Other Medicines on Your Own

If you also use steroids or other controller medicines, do not lower or stop them without your doctor’s guidance.

Contact Lenses and Eye Drops

Some eye drops contain a preservative that can build up in soft contact lenses. Remove lenses before using the drops and wait the time stated on the label before putting them back in. Do not wear contact lenses while your eyes are red or irritated.

Liver and Kidney Disease

Sodium cromoglycate is removed through the liver and kidneys. People with severe liver or kidney disease may need a lower dose and closer monitoring.

Pregnancy and Breastfeeding

• Tell your healthcare professional if you are pregnant, planning pregnancy, or breastfeeding.
• Very little of the medicine is absorbed, but decisions should still be made with a specialist.
• Uncontrolled asthma and severe allergy can also pose risks in pregnancy.

Children and Older Adults

• Children: Approved ages and forms vary by product. Some nasal, nebulized, and oral forms are used in young children, but only as directed.
• Older adults: Other health conditions and medicines should be reviewed.

Conditions to Discuss Before Starting

Tell your healthcare professional if you have, or have had:

• Asthma or sensitive airways
• Liver or kidney disease
• Heart rhythm problems (relevant to a few older inhalers)
• An allergy to sodium cromoglycate or ingredients in the product, including preservatives
• Eye infections or contact lens use (for eye drops)

Monitoring

Your care team may:

• Track symptoms, lung function tests, and how often you need quick-relief medicine
• Review how well nasal, eye, or stomach symptoms are controlled
• Check inhaler, nebulizer, or nasal spray technique at follow-up visits

Safety Information From Regulators

Regulators note that sodium cromoglycate is a preventive medicine that should be used regularly and is not for treating sudden symptoms. Read the current prescribing information and patient leaflet that come with your medicine.

Who This Medication Is For

Sodium cromoglycate is intended for:

• Children and adults with asthma who need preventive treatment, as decided by their healthcare professional and within the label’s age limits.
• People who get airway tightening with exercise or known triggers and need prevention.
• People with allergic rhinitis or allergic conjunctivitis who need prevention or relief of nose or eye symptoms.
• People with mastocytosis, where labeled, as directed by a specialist.

It is often chosen when a gentle preventive medicine is wanted, such as in young children, or when other treatments are not suitable. A specialist or primary care provider decides if it is appropriate after reviewing symptoms, prior treatments, and overall health.

Who Should Not Take Sodium Cromoglycate (Cromolyn)

Do not use this medicine if:

• You are allergic to sodium cromoglycate or any other ingredient in the product.
• You need quick relief of a sudden asthma attack. Sodium cromoglycate is not for this purpose.

Important Precautions

Use extra caution and speak with your specialist if you have asthma that is not well controlled, liver or kidney disease, or an eye infection. Use extra caution in young children and when using more than one asthma or allergy medicine.

What to Do If You Miss a Dose

• If you miss a dose, take it as soon as you remember, unless it is almost time for the next dose. In that case, skip the missed dose.
• Never double up or take extra doses to catch up.
• For exercise prevention, use it shortly before activity, as directed. Do not use extra doses to make up for a missed one.
• If you often forget doses or are unsure what to do, contact a licensed healthcare professional or pharmacist.
• If symptoms worsen after a missed dose, follow your asthma or allergy action plan and get medical help if needed.

Related medications to Sodium Cromoglycate (Cromolyn)

Other medicines used for similar conditions include:

• For asthma: inhaled corticosteroids, ICS/LABA combination inhalers, and leukotriene receptor antagonists such as montelukast
• For allergic rhinitis: nasal corticosteroid sprays, antihistamine tablets or nasal sprays, and combination nasal sprays
• For allergic conjunctivitis: antihistamine eye drops (such as olopatadine or ketotifen), other mast cell stabilizer drops, and lubricating drops
• For mastocytosis and related conditions: antihistamines and other medicines directed by a specialist

These options differ in how they are used, how they work, and their side effects. Do not switch or stop treatment without guidance. Any change should be made after consulting a licensed medical specialist.

Storage Instructions

• Store at room temperature, usually about 59°F to 86°F (15°C to 30°C), unless the label says otherwise.
• Keep products dry, protected from light and heat, and away from freezing.
• Nebulizer vials: keep them in the protective foil pouch until use, and follow the label for how long they can be used once removed from the pouch.
• Nasal spray: keep the cap on, store upright, and follow the label for how long the bottle can be used after opening.
• Eye drops: keep the bottle tightly closed, and follow the label for how long drops can be used after opening, since opened drops should not be kept indefinitely.
• Inhaler: the canister is pressurized, so do not puncture it, burn it, or keep it near heat or open flame.
• Keep out of reach and sight of children and pets. Never share your medicine with others.
• Dispose of expired or unused medicine as advised by your pharmacist or local disposal program.

Disclaimer:

This page is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Patients must consult a licensed pulmonologist, allergist, or other relevant medical specialist before starting, changing, or stopping treatment. Treatment decisions must be based on a full clinical evaluation by a qualified specialist. Always follow the prescribing information and patient leaflet provided with your medicine.