Arrhythmia drug-related

Procainamide INa (primary) and IKr (secondary) blockade Slows conduction velocity and pacemaker rate prolongs action potential duration and dissociates from INa channel with intermediate kinetics direct depressant effects on sinoatrial (SA) and atrioventricular (AV) nodes Most atrial and ventricular arrhythmias drug of second choice for most sustained ventricular arrhythmias associated with acute myocardial infarction Oral, IV, IM eliminated by hepatic metabolism to /V-acetylprocainamide (NAPA see text) and renal elimination NAPA implicated in torsade de pointes in patients with renal failure Toxicity Hypotension long-term therapy produces reversible lupus-related symptoms... 

In Phase II clinical trials, emetine as an antineoplastic agent was shown to exert moderate and reversible toxicity, consisting mainly of muscular weakness, local pain, and transient cardiac arrhythmias. However, no complete or partial regression of solid tumors was observed.The studies so far do not appear to indicate that emetine treatment results in tumor response with an acceptable degree of drug related toxicity in epidermoid bronchogenic carcinoma. ... 

Decreased Cardiac Output related to adverse drug reactions (drug-induced arrhythmias)... 

Amphotericin B is the mainstay of treatment of patients with severe endemic fungal infections. The conventional deoxycholate formulation of the drug can be associated with substantial infusion-related adverse effects (e.g., chills, fever, nausea, rigors, and in rare cases hypotension, flushing, respiratory difficulty, and arrhythmias). Pre-medication with low doses of hydrocortisone, acetaminophen, nonsteroidal anti-inflammatory agents, and meperidine is common to reduce acute infusion-related reactions. Venous irritation associated with the drug can also lead to thrombophlebitis, hence central venous catheters are the preferred route of administration in patients receiving more than a week of therapy. 

The pharmacological inhibition of the serotonin eliminating enzyme MAO is used in the therapy of depression and hypertension. Tranylcypromine is an irreversible unselective MAO inhibitor which displays numerous interactions with amine-containing food and monoamine-related drugs, resulting in evenmally fatal hypertensive crisis, cranial hemorrhage, arrhythmias and seizure can occur. The coadministration with speciflc serotonin reuptake inhibitors (SSRI) can result in similar effects and is therefore contraindicated. Moclobemide, on the other hand, is a reversible inhibitor of MAOa, one of the two enzyme subtyppes (MAOa, MAOb) which is void of most interactions see with tranylcypromine. 

The acute effects of psychomotor stimulant overdoses are related to their CNS stimulant properties and may include euphoria, dizziness, tremor, irritability, and insomnia. At higher doses, convulsions and coma may ensue. These drugs are cardiac stimulants and may cause headache, palpitation, cardiac arrhythmias, anginal pain, and either hypotension or hypertension. Dextroamphetamine produces somewhat less cardiac stimulation. Chronic intoxication, in addition to these symptoms, commonly results in weight loss and a psychotic reaction that is often diagnosed as schizophrenia. 

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