Meperidine dosage

Relief of pain - While subcutaneous administration is suitable for occasional use, IM administration is preferred for repeated doses. If IV administration is required, decrease dosage and inject very slowly, preferably using a diluted solution. Meperidine is less effective when administered orally than when given parenterally. Reduce proportionately (usually by 25% to 50%) when administering concomitantly with phenothiazines and other tranquilizers. 

Seizures Seizures may be aggravated or may occur in individuals with or without a history of convulsive disorders if dosage is substantially increased above recommended levels because of tolerance. Observe patients with known seizure disorders closely for hydromorphone-, meperidine-, morphine-, or tramadol-induced seizure activity. 

Meperidine can be taken orally or injected. Oral forms include tablets and syrup. Dosages of tablets range from 25 mg to 100 mg meperidine per tablet. The syrup form contains 50 mg meperidine per 5 ml. The typical dosage is from 50 mg to 150 mg every three to four hours. 

Injections of meperidine can be given intramuscularly (in the muscle), subcutaneously (under the skin), and intravenously (directly into the bloodstream). The body responds more readily to meperidine when it is injected, so dosages are usually about half that of the oral form, again every three to four hours. As with other opioids, intravenous administration of meperidine is often given at a low, continual dose. 

V. Das Gupta, Quantitation of meperidine hydrochloride in pharmaceutical dosage forms by HPLC, J. Pharm. Sci., 72 695 (1983). 

Diphenoxylate is a meperidine congener that is approved for the treatment of diarrhea (see Chapter 37). Diphenoxylate hydrochloride is available only in combination with atropine sulfate (LOMOTIL, Others). The recommended daily dosage of diphenoxylate for the treatment of diarrhea in adults is 20 mg in divided doses. Difenoxin (motofen), a metabolite of diphenoxylate, has actions similar to those of the parent compound. 

Thus the reflex time obtained under morphine or meperidine depends upon two variables, the control (nondrug) reflex time and the dose of drug. If the dose is kept constant, the reflex time varies linearly with the control reflex time. If the control reflex time is held constant, for example by studying the dose-effect relationship in a single animal, the reflex time is the sum of three components (1) a constant component that varies linearly with the control reflex time, (2) a component that varies linearly with the dose, and (3) a component that varies with the square of the dosage. 

Another piperidine derivative (dZ-a-1,3-dimethyl-4-phenyl-4-proprionoxy piperidine hydrochloride) in a dosage of 15 mg. raised the threshold for painful irradiation of the forehead to an extent equivalent to 10 mg. of morphine (91). The main side effects were dizziness and nausea. While less potent on a milligram basis, this derivative shows some clinical promise, since at comparable analgesic levels its side effects are small relative to morphine. Addiction liability is about equal to that of meperidine (90, 91). 

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