Meperidine indications

For the relief of pain arising from spasm of smooth muscle, as in renal or biliary colic, morphine is frequently employed. Other measures including antispasmodics such as atropine, atropine substitutes, theophylline, nitrites, and heat may be employed first however, if they are ineffective, meperidine, methadone, or opiates must be used. Morphine relieves pain only by a central action and may aggravate the condition producing the pain by exaggerating the smooth muscle spasm. Morphine may also be indispensable for the relief of pain due to acute vascular occlusion, whether this be peripheral, pulmonary, or coronary in origin. In painful acute pericarditis, pleurisy, and spontaneous pneumothorax, morphine is likewise indicated. Carefully chosen and properly spaced doses of codeine or morphine may occasionally be necessary in pneumonia to control pain, dyspnea, and restlessness. Traumatic pain arising from fractures, bums, etc., frequently requires morphine. In shock, whether due to trauma, poisons, or other causes, morphine may be required to relieve severe pain. 

Semi-synthetic and synthetic opioids (meperidine, hydrocodone, fentanyl, etc.) are the result of many attempts to produce effective yet safer analgesics. The fact that both morphine and codeine are still widely used indicates that the newer opioids have been only moderately successful. However, current knowledge of the opioid system makes the goal of producing the perfect... 

Meperidine was first synthesized in the late 1930s, and was one of the first synthetic opioids. The fact that both morphine and codeine are still widely used, though, indicates that meperidine, along with all of the opioids produced since that time, have been only modest successes. Research continues with the hope of discovering the perfect opioid analgesic. 

Evidence indicates that proper meperidine prescription for legitimate medical concerns does not greatly increase the risk of addiction and abuse. Those in the medical community agree that more education is needed by both doctors and patients to help prevent the potential for abuse and addiction, so that patients truly in need are not denied access to meperidine based on misperceptions and fear. The benefits for individuals and society are great when pain is treated safely and effectively. 

In the dog, electrically evoked contractions of the lower esophageal sphincter are inhibited by DPDPE, a response interpreted to indicate the involvement of delta opioid receptors [72]. On the other hand, DADLE increases lower esophageal sphincter pressure in the opossum. As the mu opioid agonists meperidine and buprenorphine both reduce sphincter pressure, the opposite effect of DADLE is probably mediated by delta opioid receptors [73],... 

Solt 1, Ganadry S, Weiner Z. The effect of meperidine and promethazine on fetal heart rate indices during the active phase of labor. Isr Med Assoc J 2002 4(3) 178-80. 

E Oxycodone/acetaminophen would be the most appropriate drug to start for this patient s acute postsurgical pain. The onset of action is rapid, and it can be titrated to effect. Morphine and meperidine have active metabolites that can accumulate in this patient with renal dysfunction, increasing the risk for seizures, sedation, and respiratory depression. The fentanyl patch is primarily indicated in chronic pain. The onset is slow, and the patches cannot be titrated up rapidly to cover acute pain, nor titrated down as the patient recovers and requires less opioid. 

A variety of C3 alkylated derivatives of the reversed esters of meperidine were examined (see Ref 405). Incorporation of a methyl group at C3 yields a- and jS-prodine (101 and 102, Fig. 7.23) (437). The J3 isomer (102) has five times the potency of the a isomer. X-ray crystallography and NMR indicate that the preferred conformation of the prodines is the chair form, with the phenyl ring equatorial (see Refs. 283, 438). Computational studies also indicate a preference for this conformer in the case of the reversed esters the energy differences between the equatorial and axial conformers (1.9-3.4 kcal/mol) are much greater than the differences between the two conformers of meperidine f/jand ketobemi-done(105) (410). 

The tertiary amine group in meperidine is directly titratable in non-aqueous media. Meperidine hydrochloride is likewise titratable if mercuric acetate is added to tie up the chloride ion. Standard non-aqueous titration techniques are applicable using either visual indicators or potentiometric end point detection. Several such methods for both meperidine and its hydrochloride salt have been published -. . ... 

A group of cycloalkylmethyl derivatives, of which 10 was the prototype, was prepared as indicated in Figure 1. Compound 10 was a potent meperidine antagonist comparable to 9 (R = CH3 R = CH2C = CH2). In contrast to the alkenyl-substituted benzomorphans, the members of the cycloalkylmethyl-substituted series were potent on the inclined screen and showed some degree... 

Diphenoxylate is an antidiarrheal agent. Diphenoxylate, related to meperidine, decreases motility of the GI tract. Atropine discourages deliberate overdosage of diphenoxylate. The combination is indicated as adjunctive therapy in the treatment of diarrhea. 

Naloxone, a pure narcotic antagonist (0.4 to 2.0 mg IV), is indicated for the complete or partial reversal of respiratory and CNS depression caused by naturally occurring and synthetic narcotics, including morphine, meperidine, methadone, nalbuphine, butorphanol, and pentazocine. 

Meperidine has no spasmolytic effects but an anticholinergic effect, displacing the dose-response curve for carbacholine to the right, indicating competitive antagonism. Only chemically induced spasm of guinea pig large intestine is relaxed by direct application of meperidine solution, possibly due to meperidines local activity. 

Treatment is similar to that for crotalid bites (see IV A 2 f), but clinical reports indicate that meperidine should not be used to control pain. The efficacy of crotalid antivenin for Htioderma bites has not been established. 

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