What is bitolterol mesylate, and how does it work (mechanism of action)?

Bitolterol is a bronchodilator used in the treatment of asthma. It is similar to albuterol (Ventolin). Asthma is a disorder of breathing in which there is narrowing of the airways that carry air to the lungs including the bronchi. This narrowing is caused by muscle spasm and inflammation within the airways. Bitolterol relaxes the smooth muscles surrounding these airways, increasing the diameter and thus easing the flow of air through the airways. Bitolterol probably does not affect inflammation in the lung either with asthma or other inflammatory lung disorders such as bronchitis. Nevertheless, if spasm of the airways occurs because of bronchitis, bitolterol may be useful therapy for the asthmatic component of the illness. Bitolterol is unique in that it is a "prodrug;" It must first be converted by the body into its active form. Bitolterol has a rapid onset of action (2-5 minutes), and its effects may last up to 6-8 hours. The FDA approved bitolterol in December 1984.

What brand names are available for bitolterol mesylate?

(Tornalate: This brand no longer is available in the U.S. and there are no generic versions.)

Is bitolterol mesylate available as a generic drug?


Do I need a prescription for bitolterol mesylate?


What are the side effects of bitolterol mesylate?

Side effects of bitolterol include nervousness, tremor, headache, palpitations, fast heart rate, elevated blood pressure, nausea, dizziness, and heartburn. Throat irritation and nosebleeds can also occur. Allergic reactions may occur rarely and may manifest as rash, hives, swelling, anaphylaxis, or shock. Worsening of diabetes and lowering of potassium have also been reported. In rare patients, inhaled bitolterol can paradoxically precipitate life-threatening bronchospasm.

What is the dosage for bitolterol mesylate?

The recommended adult dose for treating asthma is 2 inhalations every 8 hours. Maximum dose is 2 inhalations every 4 hours or 3 inhalations every 6 hours. This drug was not approved for use in children under 12 years old.

Which drugs or supplements interact with bitolterol mesylate?

: Tricyclic antidepressants (for example, amitriptyline [Elavil, Endep]), monoamine oxidase inhibitors (for example, tranylcypromine) should not be combined with bitolterol because of their additive effects on the vascular system (increased blood pressure, heart rate, etc.). A period of two weeks should elapse between treatment with bitolterol and tricyclic antidepressants or monoamine oxidase inhibitors.

Use of bitolterol with other stimulant medications is discouraged because of their combined effects on heart rate, blood pressure, and the potential for causing chest pain in patients with underlying coronary heart disease.

Beta-blockers, for example, propranolol (Inderal, Inderal LA), block the effect of bitolterol and may induce bronchospasm in asthmatics. Bitolterol may cause hypokalemia (low potassium). Therefore, combining bitolterol with loop diuretics, for example, furosemide (Lasix), which lowers potassium levels in the blood, may increase the likelihood of hypokalemia.


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Is bitolterol mesylate safe to take if I'm pregnant or breastfeeding?

It's not known if bitolterol is excreted in breast milk.

What else should I know about bitolterol mesylate?

What preparations of bitolterol mesylate are available?

Inhaler: 0.37 mg/Inhalation; Solution for Inhalation: 0.2%

How should I keep bitolterol mesylate stored?

Bitolterol should be stored at room temperature, 15 C to 30 C (59 F to 86 F).


Bitolterol mesylate (Tornalate) is a drug prescribed for the treatment of bronchospasms due to asthma and other respiratory illnesses. Side effects, drug interactions, warnings and precautions, and patient information should be reviewed prior to taking any medication.

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Asthma is a chronic respiratory disease. See Answer

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Medically Reviewed by John Cunha, DO

Reference: FDA Prescribing Information