Details About Overdose or Poisoning Generic Salt :: Glucagon
Drug Pharmacology ::
I. Pharmacology. Glucagonis a polypeptide hormone that stimulates the formation of adenylcyclase, which in turn increases the intracellular concentration ofcyclic adenosine monophosphate (cAMP). This results in enhancedglycogenolysis and an elevated serum glucose concentration, vascularsmooth-muscle relaxation, and positive inotropic, chronotropic, anddromotropic effects. These effects occur independently ofbeta-adrenergic stimulation (glucagon has a separate receptor on themyocardium). It may also increase arachidonic acid levels in cardiactissue via an active metabolite, miniglucagon. Arachidonic acidimproves cardiac contractility owing to its effects on calcium.Glucagon is destroyed in the GI tract and must be given parenterally.After intravenous administration, effects are seen within 1–2 minutesand persist for 10–20 minutes. The serum half-life is about 3–10minutes. Note: Glucagon usually is not consideredfirst-line therapy for hypoglycemia because of its slow onset of actionand reliance on glycogen stores. Instead, use glucose (see Glucose) ifit is available.
Drug Indications ::
Hypotension,bradycardia, or conduction impairment caused by beta-adrenergic blockerintoxication (see Beta-Adrenergic Blockers). Also consider in patientswith hypotension associated with anaphylactic or anaphylactoidreactions who may be on beta-adrenergic blocking agents.
Possiblyeffective for severe cardiac depression caused by intoxication withcalcium antagonists, tricyclic antidepressants, quinidine, or othertypes Ia and Ic antiarrhythmic drugs. Because of the benign side-effectprofile of glucagon, consider its early empiric use in any patient withmyocardial depression (bradycardia, hypotension, or low cardiac output)who does not respond rapidly to usual measures.
Tofacilitate passage of obstructed gastric foreign bodies (eg, drugpackets) through the pylorus into the intestine (based on a casereport).
Drug Contra-Indications ::
III. Contraindications. Known hypersensitivity to the drug (rare) or pheochromocytoma or insulinoma.
Drug Adverse Effects ::
IV. Adverse effects
Nauseaand vomiting by delaying gastric emptying and hypotonicity. May affectGI decontamination (activated charcoal, whole-bowel irrigation).
Use in pregnancy. FDA category B. Fetal harm is extremely unlikely (see Table III–1).
Drug Lab Interactions ::
Drug or laboratory interactions. Concurrentadministration of epinephrine potentiates and prolongs thehyperglycemic and cardiovascular effects of glucagon. It is unknown ifglucagon interferes with the effectiveness of insulin and glucosetherapy for severe calcium antagonist poisoning. Note that glucagonstimulates endogenous insulin secretion.
Drug Dose Management ::
Dosage and method of administration. Give3–10 mg IV (may also titrate with 0.05 mg/kg boluses or 3–5 mg givenover 1–2 minutes and repeated every 3 minutes until response or a totalof 10 mg), followed by 1–5 mg/h infusion (children, 0.15 mg/kg IV ortitrate with 0.05 mg/kg every 3 minutes, followed by 0.05–0.1 mg/kg/h).Up to 10 mg/h infusions have been used for adults. For very largedoses, consider using sterile water or D5W to reconstitute rather than the glycerine-containing diluent provided with the drug (eg, add 4 mg glucagon to 50 mL D5Wfor continuous infusion). Note that the optimal duration of therapy isnot known and that tachyphylaxis may occur with prolonged infusions(case report with infusion duration > 24 hours).
Drug Chemical Formulations ::
Formulations. Note: Glucagonis no longer available in 10-mg vials; instead, the 1-mg kits must beused at a considerably higher cost to attain adequate dosing for themanagement of poisonings.
Parenteral. GlucagonEmergency (or Diagnostic) Kit, 1 unit (approximately 1 mg, with 1-mLsyringe diluent with glycerine), and GlucaGen (Glucagon Hydrochloride)Diagnostic Kit (1 mg with 1 mL sterile water for diluent).
The suggested minimum stocking level to treat a 70-kg adult for the first 24 hours is 100 mg (100 kits, 1 unit each).