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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.



COMMON BRAND NAME(S): Provocholine


Methacholine is used as a test to determine if you may have asthma. It may also help to determine how serious your asthma may be.

How To Use

Ask your doctor or pharmacist how to use the medication correctly and follow all instructions carefully. The dosage is based on your medical condition and response to therapy. This medication is for inhalation use only. Do not use this medication by mouth or by injection.

Side Effects

Headaches, throat irritation, lightheadedness, and itching may occur. If any of these effects persist or worsen, notify your doctor. Tell your doctor immediately if any of these serious side effects occur: chest tightness, trouble breathing, cough, wheezing. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: epilepsy, heart disease, thyroid disease, trouble urinating (urinary obstruction), stomach ulcers, any allergies. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use, especially of: beta- blockers (e.g., nadolol, propranolol), asthma medications. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include fainting, loss of consciousness, heart attack.


Do not share this medication with others. Laboratory and/or medical tests may be performed to monitor your progress.

Missed Dose

If you miss a dose, contact your doctor or pharmacist to establish a new dosing schedule.


Before mixing, store the dry powder and mixing solution at 59 to 86 degrees F (15 to 30 degrees C). Once mixed, the solution is good for up to 14 days and may be refrigerated (36 to 46 degrees F or 2 to 8 degrees C). Discard any unused portion of the vials.