Clinical Manifestations: Mainly hypotension and bradycardia. On EKG, can see PR prolongation leading ot AV block, and sometimes QRS prolongation (with certain beta blockers like sotalol). Ddx includes overdose of calcium channel blockers, digoxin, and cholinergic agents. Management: Side effects: Anticholinergic effects = 1) CNS effects, 2) GI – decreased saliva, nausea, vomiting, ileus, 3) GU – urinary retention, 4) CV – tachycardia (obviously) and arrhythmias, 5) Eyes – blurry vision 2. Glucagon – 5 mg bolus over 1 minute, can repeat 10-15 minutes later. If positive response, can start an infusion at 2-5 mg/hour. Activates adenylate cyclase to raise c AMP levels, which increases intracellular Ca releat. This increases contractility and possibly heart rate. IV calcium – can give Ca Cl (if have central line) or Ca Gluconate (if peripheral line). Even though this is considered a 1st-line “antidote” there is actually limited data to support this. Epinephrine or Dopamine, due to both inotropic effect and vasoconstriction. White to off-white, circular, biconvex uncoated tablets impressed “50” and the identifying letters “MJ” on either side of a central division line on one face, plain on the reverse. 3) Cardiac arrhythmias (especially supraventricular tachyarrhythmias). Metoprolol tartrate has been shown to reduce mortality when administered to patients with acute myocardial infarction. The score line is only to facilitate breaking for ease of swallowing and not to divide into equal doses. The following dosage regimes are intended only as a guideline and should always be adjusted to the individual requirements of the patient. This may be increased, if necessary, to 200mg daily in single or divided doses. Pain relief may also decrease the need for opiate analgesics. 6) Early intervention of metoprolol tartrate in acute myocardial infarction reduces infarct size and the incidence of ventricular fibrillation. Combination therapy with a diuretic or vasodilator may also be considered to further reduce blood pressure. Metoprolol may be administered with benefit both to previously untreated patients with hypertension and to those in whom the response to previous therapy is inadequate. In the latter type of patient the previous therapy may be continued and metoprolol added in to the regime with adjustment of the previous therapy if necessary. In general a significant improvement in exercise tolerance and reduction of anginal attacks may be expected with a dose of 50-100mg twice daily.
Beta blockers act as competitive inhibitors of catecholamines, exerting their effects at both central and peripheral receptors. Blockade of beta-receptors results in decreased production of intracellular cyclic adenosine monophosphate (c AMP) with a resultant blunting of multiple metabolic and cardiovascular effects of circulating catecholamines. Beta1-blockers reduce heart rate, blood pressure, myocardial contractility, and myocardial oxygen consumption. Beta2-receptor blockade inhibits relaxation of smooth muscle in blood vessels, bronchi, the gastrointestinal system, and the genitourinary tract. In addition, beta-adrenergic receptor antagonism inhibits both glycogenolysis and gluconeogenesis, which may result in hypoglycemia. Bradycardia: Hypotension: Seizures: EKG changes: Hypothermia, hypoglycemia can occur but are less common. Bradycardia, by itself, is not necessarily helpful as a warning sign because slowing of the heart rate and damping of tachycardia in response to stress is observed with therapeutic doses. A short cut review was carried out to establish whether the intravenous glucagon can support blood pressure in β blocker overdose. A total of 51 papers were found using the reported search, of which six presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. A 25 year old patient presents to the emergency department two hours after taking a significant overdose of propanolol. She is bradycardic and hypotensive despite initial resuscitation with oxygen and intravenous fluids. You have heard of treatment with intravenous glucagon but wonder if it has been of any proved benefit. In [symptomatic significant beta-blocker overdose] is [intravenous glucagon] effective at [reversing the induced hypotension]? [exp glucagon Or glucagon.mp] AND [ AND OR ] Altogether 51 papers were found of which six were deemed relevant. No clinical trials were identified and all the papers available were case reports. No clinical trials or even case controlled studies have been published. There is therefore only anecdotal evidence for the use of glucagon.
Beta-blockers are a type of drug used to treat high blood pressure. They are one of several classes of medicines used to treat the heart and related conditions. Beta-blocker overdose occurs when someone takes more than the normal or recommended amount of this medicine. This is for information only and not for use in the treatment or management of an actual overdose. DO NOT use it to treat or manage an actual overdose. If you or someone you are with overdoses, call your local emergency number (such as 911), or your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. The specific ingredient that can be poisonous in these drugs varies among the different drug makers. The main ingredient is a substance that blocks the effects of a hormone called epinephrine. Your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1800-222-1222) from anywhere in the United States. All local poison control centers in the United States use this national number. This national hotline will let you talk to experts in poisoning. You should call if you have any questions about poisoning or poison control. You can call for any reason, 24 hours a day, 7 days a week. Published reports of beta blocker ingestions in adults are retrospectively reviewed to determine at what point postingestion symptoms develop. Thirty-nine symptomatic beta blocker ingestions were found. Thirty-one (80%) of those who demonstrated symptoms did so within 2 h of ingestion. This number rose to thirty-eight (97%) by 4 h postingestion. Only one patient developed symptoms after more then 4 h of asymptomatic observation. The development of bradycardia and first degree atrioventricular block during observation appeared to predict toxicity in this patient who suddenly developed hypotension 6 h postingestion. No patient required treatment for delayed cardiovascular depression if they remained asymptomatic during a 4-h period of observation postingestion and demonstrated a normal electrocardiogram throughout. Whether the risk of delayed onset of toxicity after 6 h of asymptomatic observation is sufficiently low to warrant “medical clearance” requires further investigation.
A 42-Year-Old Woman with a Beta Blocker Overdose. beta blocker overdose first requires a dis- cussion. treatment of a massive metoprolol overdose using. The goal of therapy in beta-blocker toxicity is to restore perfusion to critical organ systems by increasing cardiac output. This may be.