Glycopyrronium bromide is a medication of the muscarinic anticholinergic group. It does not cross the blood–brain barrier and consequently has no to few central effects. It is available in by mouth, intravenous, topical, and inhalated forms. It is a synthetic quaternary ammonium. Glycopyrronium bromide is a medication of the muscarinic anticholinergic group. It does not cross the blood–brain barrier and consequently has no to few central effects. It is available in by mouth, intravenous, topical, and inhalated forms. It is a synthetic quaternary ammonium. It was developed by Sosei and licensed to Novartis in 2005. The cation, which is the active moiety, is called glycopyrronium (INN) or glycopyrrolate (USAN). In June 2018, glycopyrronium was approved by the FDA to treat excessive underarm sweating, becoming the first drug developed specifically to reduce excessive sweating. In anesthesia, glycopyrronium injection can be used as a before surgery in order to reduce salivary, tracheobronchial, and pharyngeal secretions, as well as decreasing the acidity of gastric secretion. It is also used in conjunction with neostigmine, a neuromuscular blocking reversal agent, to prevent neostigmine's muscarinic effects such as bradycardia. It is also used to reduce excessive saliva (sialorrhea), and Ménière's disease. It decreases acid secretion in the stomach and so may be used for treating stomach ulcers, in combination with other medications. It has been used topically and orally to treat hyperhidrosis, in particular, gustatory hyperhidrosis. In inhalable form it is used to treat chronic obstructive pulmonary disease (COPD). Doses for inhalation are much lower than oral ones, so that swallowing a dose will not have an effect. Since glycopyrronium reduces the body's sweating ability, it can even cause hyperthermia and heat stroke in hot environments. Dry mouth, difficulty urinating, headaches, diarrhea and constipation are also observed side effects of the medication. The medication also induces drowsiness or blurred vision, an effect exacerbated by the consumption of alcohol.