A comparison of metoclopramide and lidocaine for preventing pain on injection of diazepam.

UNLABELLED: We compared the ability of metoclopramide with IV lidocaine pretreatment to abolish pain from a diazepam injection. In a randomized, prospective, double-blinded, placebo-controlled clinical trial, 159 patients (ASA physical status I and II), aged 20-70 yr old, were allocated to one of three groups. Placebo and study drugs were injected IV immediately before 0.1 mg/kg of diazepam into a dorsal hand vein. Patients in Groups 1, 2, and 3 received 2 mL of placebo, 2 mL of lidocaine 1%, and 2 mL of metoclopramide (10 mg), respectively. The patient's response was graded using a 4-point scale. Any score other than 0 represented pain on injection. We observed that the incidence of pain on diazepam injection was 83% in the placebo group, which was decreased to 70% and 39% in patients pretreated with metoclopramide and lidocaine, respectively. Although there was no significant difference in the incidence of pain in Groups 1 and 3 (P > 0.05), Group 3 showed significantly less patients with severe pain scores than Group 1 as diazepam was injected (P < 0.000). Group 2 showed a significantly less frequent incidence of pain than the saline (P < 0.000) and the metoclopramide (P < 0.002) groups as diazepam was injected. The intensity of pain in Group 2 was significantly less than Group 3 (P = 0.012). The intensity of diazepam injection pain was intense with placebo as compared with other groups (P < 0.000). Metoclopramide, rather than lidocaine pretreatment, may be a reasonable analgesic alternative for painful injections.

IMPLICATIONS: Metoclopramide, rather than lidocaine pretreatment, may be a reasonable analgesic alternative to decrease pain from a diazepam injection, especially when there is a medical condition in which lidocaine should be used very cautiously.