Drugs which decrease the propulsion of intestinal contents may exaggerate the effects of diphenoxylate and cause constipation. Such drugs include hyoscyamine (Levsin; Cystospaz), antihistamines such as hydroxyzine (Vistaril, Atarax) and diphenhydramine (Benadryl), opiate agonists such as oxycodone (Percocet) and hydrocodone (Vicodin, Norco, etc.), some phenothiazine antipsychotics such as chlorpromazine (Thorazine), thioridazine (Mellaril) and triflupromazine (Stelazine), and some tricyclic antidepressants such as amitriptyline (Elavil, Endep), amoxapine (Asendin), clomipramine (Anafranil), doxepin (Sinequan), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil).
Quick GuideDigestive Disease Myths Pictures Slideshow: Common Misconceptions
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