Details About Overdose or Poisoning Generic Salt :: Metoclopramide
Drug Pharmacology ::
I. Pharmacology. Metoclopramideis a dopamine antagonist with antiemetic activity at the chemoreceptortrigger zone. It also accelerates GI motility and facilitates gastricemptying. The onset of effect is 1–3 minutes after intravenousadministration, and therapeutic effects persist for 1–2 hours after asingle dose. The drug is excreted primarily by the kidney. Theelimination half-life is about 5–6 hours but may be as long as 14.8hours in patients with renal insufficiency and 15.4 hours in patientswith cirrhosis.
Drug Indications ::
Metoclopramideis used to prevent and control persistent nausea and vomiting,particularly when the ability to administer activated charcoal (eg,treatment of theophylline poisoning) or another oral antidotal therapy(eg, acetylcysteine for acetaminophen poisoning) is compromised.
Theoretical(unproved) use to stimulate bowel activity in patients with ileus whorequire repeat-dose activated charcoal or whole-bowel irrigation.
Drug Contra-Indications ::
Known hypersensitivity to the drug; possible cross-sensitivity with procainamide.
Mechanical bowel obstruction or intestinal perforation.
Pheochromocytoma (metoclopramide may cause hypertensive crisis).
Drug Adverse Effects ::
IV. Adverse effects
Sedation, restlessness, fatigue, and diarrhea may occur.
Extrapyramidalreactions may result, particularly with high-dose treatment. Pediatricpatients appear to be more susceptible. These reactions may beprevented by pretreatment with diphenhydramine (see Diphenhydramine).
May increase the frequency and severity of seizures in patients with seizure disorders.
Parenteral formulations that contain sulfite preservatives may precipitate bronchospasm in susceptible individuals.
E. Use in pregnancy. FDA category B. Not likely to cause harm when used as short-term therapy (see Table III–1).
Drug Lab Interactions ::
Drug or laboratory interactions
Additive sedation in the presence of other CNS depressants.
Riskof extrapyramidal reactions may be increased in the presence of otherdopamine antagonist agents (eg, haloperidol and phenothiazines).
Inone study involving hypertensive patients, metoclopramide enhanced therelease of catecholamines. As a result, the manufacturer advisescautious use in hypertensive patients and suggests that the drug shouldnot be used in patients taking monoamine oxidase inhibitors.
Agitation, diaphoresis, and extrapyramidal movement disorder werereported in two patients taking selective serotonin reuptake inhibitors(sertraline, venlafaxine) who received IV metoclopramide.
E. The drug may enhance the absorption of ingested drugs by promoting gastric emptying.
F. Anticholinergic agents may inhibit bowel motility effects.
G.Numerous IV incompatibilities: calcium gluconate, sodium bicarbonate,cimetidine, furosemide, and many antibiotic agents (eg, ampicillin,chloramphenicol, erythromycin, penicillin G, potassium, tetracycline).
Drug Dose Management ::
Dosage and method of administration
Low-dose therapy. Effective for mild nausea and vomiting. Give 10–20 mg IM or slowly IV (children, 0.1 mg/kg/dose).
High-dose therapy. Forcontrol of severe or persistent vomiting. For adults and children, give1–2 mg/kg IV infusion over 15 minutes in 50 mL dextrose or saline. Maybe repeated twice at 2- to 3-hour intervals.
1. Metoclopramideis most effective if given before emesis or 30 minutes beforeadministration of a nausea-inducing drug (eg, acetylcysteine).
2. If no response to initial dose, may give additional 2 mg/kg and repeat every 2–3 hours up to maximum 12 mg/kg total dose.
3. Pretreatment with 50 mg (children, 1 mg/kg) of diphenhydramine (see Diphenhydramine) helps prevent extrapyramidal reactions.
4. Reduce dose by one-half in patients with renal insufficiency.
Drug Chemical Formulations ::
Parenteral. Metoclopramidehydrochloride (Reglan, others), 5 mg/mL; 2-, 10-, 30-, 50-, and 100-mLvials. Also available in preservative-free 2-, 10-, and 30-mL vials and2- and 10-mL ampules.
The suggested minimum stocking level to treat a 70-kg adult for the first 24 hours is 1000 mg (four vials, 50 mL each, or equivalent).