Help!!! Glucagon with Beta blocker OD

[medicv83]

Ok yall, This is not a fun question, but I need some help figuring something out. What is the action of Glucagon in a Beta Blocker overdose. Please help me yall.

[AZCEP]

The same as it's action any other time you use it.

www.rxlist.com/cgi/generic/gluca.htm

[logos]

The hypothesis is that since the glucagon receptor is a G-protein coupled receptor that leads to the activation of adenylate cyclase and thus the formation of cAMP (cyclic AMP), giving glucagon will oppose the effect of B-blockers which block the B-receptors which are another type of G-protein coupled receptor (and thus also lead to activation of adenylate cyclase and cAMP production when agonist bound.

I'm not sure how strong the evidence backing the proposed benefit is. I doubt very strong, but at least its something that can be done. The other option would be to give B-agonists (isoproterenol is a pure beta agonist IIRC), but I suspect this is considered a last ditch effort in cases of severe overdose.

[medicv83]

Purrciate it buddy, thanks

[jsadin]

http://www.theannals.com/cgi/content/abstract/18/5/394

Two cases of severe beta-blocker overdose are presented that were treated successfully with glucagon therapy. The effects of glucagon in reversing the cardiovascular depression of profound beta-blockade, including its mechanism of action, onset and duration of action, dosage and administration, cost and availability, and side effects are reviewed. Medical complications of beta-blocker overdose include hypotension, bradycardia, heart failure, impaired atrioventricular conduction, bronchospasm and, occasionally, seizures. Atropine and isoproterenol have been inconsistent in reversing the bradycardia and hypotension of beta-blocker overdose. Glucagon increases heart rate and myocardial contractility, and improves atrioventricular conduction. These effects are unchanged by the presence of beta-receptor blocking drugs. This suggests that glucagon's mechanism of action may bypass the beta-adrenergic receptor site. Because it may bypass the beta-receptor site, glucagon can be considered as an alternative therapy for profound beta-blocker intoxications. The doses of glucagon required to reverse severe beta-blockade are 50 micrograms/kg iv loading dose, followed by a continuous infusion of 1-15 mg/h, titrated to patient response. Glucagon-treated patients should be monitored for side effects of nausea, vomiting, hypokalemia, and hyperglycemia. The high cost and limited availability of glucagon may be the only factors precluding its future clinical acceptance.

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[medicv83]

You da man. Thanks