Dicyclomine hydrochloride

The answer is c. (Hardman, pp 156-158.) A wide variety of clinical conditions are treated with antimuscarinic drugs. Dicyclomine hydrochloride and methscopolamine bromide are used to reduce Gl motility, although side effects—dryness of the mouth, loss of visual accommodation, and difficulty in urination—may limit their acceptance by patients. Cyclopentolate hydrochloride is used in ophthalmology for its mydriatic and cycloplegic properties during refraction of the eye. Trihexyphenidyl hydrochloride is one of the important antimuscarinic compounds used in the treatment of parkinsonism. For bronchodilation in patients with bronchial asthma and other bronchospastic diseases, ipratropium bromide is used by inhalation. Systemic adverse reactions are low because the actions are largely confined to the mouth and airways. 

Other agents, including tricyclic antidepressants, propantheline, flavox-ate, hyoscyamine, and dicyclomine hydrochloride, are less effective, not safer, or have not been adequately studied. 

Tertiary amines used for their antispasmodic properties are dicyclomine hydrochloride (Ben-tyl, others), oxyphencyclimine hydrochloride (daricon), flavoxate hydrochloride (Uripas), and oxyburynin chloride (Ditropan). The latter two are indicated specifically for urological disorders. These agents appear to exert some nonspecific direct relaxant effect on smooth muscle. In therapeutic doses they decrease spasm of the gastrointestinal tract, biliary tract, ureter, and uterus characteristic atropine-like effects on the salivary glands and the eye also are seen with oxybutynin. 

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