The popular asthma drug, albuterol, may actually constrict airways. From Asthma Inhaler Ingredient May Counteract Benefits:
One of the drugs used in inhalers to treat asthma can counteract the benefits of the others, U.S. researchers reported on Tuesday.
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The ingredient is albuterol, in a class of medications called beta-agonists. In inhalers it is combined with steroids to open airways and ease the gasping of patients with asthma and other lung diseases.
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The trouble, said Ameredes, is that albuterol has two forms or isomers — a so-called left-handed version and a right-handed one. These isomers refer to the molecular structure.The “right” version relaxed the airways when used with the steroid dexamethasone but the “left” version in fact increased the inflammatory signals that caused the airways to tighten, he said.
That “left” version sounds pretty sinister.