Atropine is a natural compound proposed for asthma, but given its side effects (especially inhibition of secretion), less soluble quaternary compounds (e.g. ipratropium bromide) have been developed. Anticholinergic drugs are specific antagonists of muscarinic receptors and inhibit bronchoconstriction induced by stimulation of cholinergic nerves. There is a slight decrease in bronchial tone due to tonic cholinergic nerve impulses that cause the release of acetylcholine in the smooth muscles of the respiratory tract, and the cholinergic reflex of bronchoconstriction is triggered by irritating substances, cold air and stress. Although anticholinergics protect against an attack caused by sulfur dioxide and emotional factors, they are less effective against antigens, physical exertion, and smoke – they suppress only reflex cholinergic bronchoconstriction, but they do not have a significant blocking effect on the immediate effects of inflammatory mediators such as histamine and leukotrienes. Clinical use of atropine Ipratropium bromide and oxytropium bromide are administered by inhalation 3 or 4 times a day, while tiotropium bromide is prescribed 1 time per day. • In asthmatics, anticholinergics are less effective than b2-agonists, and to a lesser extent protect against various bronchoconstrictive factors. • Nebulized anticholinergics are effective in case of asthma, but to a lesser extent than b2-agonists. Anticholinergic drugs have an additive effect on b2-agonists in emergency and ongoing treatment, and therefore the question of their use should be considered with inadequate asthma control, especially with the development of side effects of theophylline or inhaled b2-agonists. Side effects of atropine: • Inhaled anticholinergics are well tolerated, and systemic side effects rarely occur because systemic absorption practically does not occur. • Ipratropium bromide, even at high doses, does not have a clear effect on secretion in the airways. • Nebulized ipratropium bromide accelerates the development of glaucoma in elderly patients as a result of the direct action of the nebulized drug on the eyes; this is avoided using a mouthpiece rather than a face mask. • The paradoxical bronchoconstriction on ipratropium bromide, especially when using a nebulizer, was mainly explained by the hypotonicity of the first solutions in the nebulizer and the increased effect of antibacterial drugs such as benzalkonium chloride; modern drugs solve these problems.