Procainamide Beta blockers

PROCAINAMIDE BETA-BLOCKERS Risk of bradycardia (occasionally severe), 1 BP and heart failure Additive negative inotropic and chronotropic effects Monitor PR, BP and ECG closely watch for development of heart failure... 

Digoxin toxicity use of quinidine, procainamide, beta blockers, calcium channel blockers, or amiodarona nel blockers, and beta blockers. 

Propranolol may increase procainamide plasma levels. Additive cholinergic effects may occur when procainamide is administered with other drugp with anticholinergic effects. There is the potential of additive cardiodepressant effects when procainamide is administered with lidocaine. When a beta blocker, such as Inderal, is administered with lidocaine, there is an increased risk of lidocaine toxicity. 

Drugs that may affect procainamide include amiodarone, anticholinergics, antiarrhythmics, beta-blockers, ethanol, histamine H2antagonists, propranolol,... 

Drugs that may affect lidocaine include beta-blockers, cimetidine, procainamide, tocainide, and succinylcholine. 

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

PROPAFENONE I. ANTIARRHYTHMICS - disopyra-mide, procainamide 2. ANTIBIOTICS - macrolides (especially azithromycin, clarithromycin, parenteral erythromycin, telithromycin), quinolones (especially moxifloxacin), quinupristin/ dalfopristin 3. ANTICANCER AND IMMUNOMODULATING DRUGS -arsenic trioxide 4. ANTIDEPRESSANTS - TCAs, venlafaxine 5. ANTIEMETICS-dolasetron 6. ANTIFUNGALS-fluconazole, posaconazole, voriconazole 7. ANTIHISTAMINES - terfenadine, hydroxyzine, mizolastine 8. ANTI-M ALARIALS - artemether with lumefantrine, chloroquine, hydroxychloroquine, mefloquine, quinine 9. ANTIPROTOZOALS - pentamidine isetionate 10. ANTIPSYCHOTICS-atypicals, phenothiazines, pimozide II. BETA-BLOCKERS - sotalol 12. BRONCHODILATORS -parenteral bronchodilators 13. CNS STIMULANTS - atomoxetine Risk of ventricular arrhythmias, particularly torsades de pointes Additive effect these drugs prolong the Q-T interval. Also, amitriptyline, clomipramine and desipramine levels may be t by propafenone. Amitriptyline and clomipramine may t propafenone levels. Propafenone and these TCAs inhibit CYP2D6-mediated metabolism of each other Avoid co-administration... 

Patients should be advised to rest and to avoid extreme heat. They should be warned that symptoms may be aggravated by illness, stress, malnutrition, pain, or surgery. Various drugs have been shown to worsen symptoms of myasthenia gravis. These include the aminoglycoside antibiotics such as tobramycin, gentamicin, and neomycin tetracyclines such as doxycycline and minocycline class 1 antiarrhythmics such as lidocaine, quinidine, and procainamide magnesium in calcium and multivitamin supplements beta-blockers such as timolol and propranolol calcium channel blockers such as verapamil and penicillamine. 

The negative inotropic effects of class I antidysrhythmic agents, such as disopyramide, procainamide, quinidine, and tocainide can be accentuated by beta-blockers this is most pronounced in patients with pre-existing myocardial disease and can result in left ventricular failure or even asystole (413). Digoxin can obviate the negative inotropic effect of beta-blockers in patients with poor left ventricular function. 

The following drugs have been commonly associated with inducing, aggravating or unmasking SLE beta-blockers, carbamazepine, chlorpromazine, estrogens, griseofulvin, hydralazine, isoniazid (INH), lithium, methyldopa, minoxidil, oral contraceptives, penicillamine, phenytoin (diphenylhydantoin), procainamide, propylthiouracil, quinidine, and testosterone. 

Answer E. Cimetidine is an inhibitor of the hepatic cytochrome P450 isoform that metabolizes phenytoin, consequently decreases its clearance, and thus increases its elimination half-life. The hepatic metabolism of many other drugs can be inhibited by cimeti-dine, possibly necessitating dose reductions to avoid toxicity, including beta blockers, iso-niazid, procainamide, metronidazole, tricyclic antidepressants, and warfarin. 

The Multicenter Automatic Defibrillator Trial (MADIT) randomized 196 patients with prior MI, class I—III congestive HF, a LVEF <35%, NSVT, and inducible VT on EP study that was not suppressible with procainamide, to an ICD or conventional therapy (16). Most patients in the conventional therapy arm received amiodarone. The trial was stopped early as it demonstrated a statistically significant, and impressive, 54% reduction in total mortality in the ICD arm at 27 months (16% and 39% in the ICD and conventional therapy groups, respectively). MADIT is notable in that it only enrolled a small number of patients and did not have a control group. In addition, more patients in the ICD group received beta-blockers. 

A. Check blood pressure and pulse rate and rhythm. Perform cardiopulmonary resuscitation (CPR) if there is no pulse and perform advanced cardiac life support (ACLS) for arrhythmias and shock. Note that some ACLS drugs may be ineffective or dangerous in patients with dmg- or poison-induced cardiac disorders. For example, procainamide is contraindicated in patients with tricyclic antidepressant overdose, and atropine and isoproterenol are ineffective in patients with beta-blocker poisoning. 

Propranolol and other beta blockers Encainide and flecainide Quinidine, procainamide, and disopyramide Tricyclic antidepressants... 

Beta blockers (mainly propranolol) Encalnide and flecalnide Quinidine, procainamide, and disopyramide Propoxyphene Tricyclic antidepressants Others Barbiturates... 

If cardiac function is preserved, treatment priority calcium channel blocker, beta blocker, digoxin, and cardioversion then consider procainamide, or amiodarone if each preceding treatment is ineffective in rhythm conversion. 

If polymorphic QRS complexes and normal QT interval, administer beta blockers, lidocaine, amiodarone, procainamide, or sotalol (follow ACLS protocol) if drug is unsuccessful, cardioversion. 

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