comparison of effect of morphine-chlorpheniramine combined versus morphine alone in alleviating acute renal colic pain: a randomized clinical trail

background: renal colic is a significant painful condition that needs urgent and influential treatment by proper analgesics. the studies showed that histamine receptors expressed in the ureter and causes strong peristaltic contractions in the ureter. the concept of this study assumed that chlorpheniramine, propylamine h1-receptor antagonist (antihistamine), may have an effective role in management of renal colic pain. methods: in this randomized clinical trial, 112 patients with renal colic were divided into 2 groups, the intervention group (group a) received 1cc of intravenous chlorpheniramine along with 5 mg morphine. while group b patients received 1 cc of isotonic solution along with 5 mg morphine. the pain was measured by visual analog scale, before the treatment and 4 time points after treatment including; 15, 30, 45, and 60 minutes after intervention. results: patients’ mean age was 40.20 ± 7.21. the amount of pain score, immediately before starting intervention, time point of 15 minutes and 60 minutes after had no statistical significant differences between 2 groups, however, there were significant differences in the time point of 30 and 45 minutes. moreover the results showed that use of chlorpheniramine are in relation with lowering incidence of nausea,vomiting, as well as decreases the morphine required dose. conclusions: our results indicated that chlorpheniramine may be an effective agent in reliving renal colic pain. moreover it has been shown that the use of chlorpheniramine are in relation with lowering incidences of nausea, vomiting, as well as also decreases the morphine required dose. we conclude that additional chlorpheniramine can lower the needed dose for opioids and can probably diminish the opioids adverse effects.