Therapeutic: antiarrhythmics (class IC)
Life-threatening ventricular arrhythmias, including ventricular tachycardia. Supraventricular tachyarrhythmias, including Paroxysmal supraventricular tachycardia (PSVT), Paroxysmal atrial fibrillation/flutter (PAF). Unlabeled Use: Single-dose treatment of atrial fibrillation.
Slows conduction in cardiac tissue by altering transport of ions across cell membranes. Therapeutic Effects: Suppression of arrhythmias.
Adverse Reactions/Side Effects
CNS: dizziness, anxiety, fatigue, headache, mental depression. EENT: blurred vision, visual disturbances. CV: ARRHYTHMIAS, CHEST PAIN, CHF. GI: anorexia, constipation, drug-induced hepatitis, nausea, stomach pain, vomiting. Derm: rashes. Neuro: tremor.
PHYSICAL THERAPY IMPLICATIONS
Examination and Evaluation
Assess heart rate, ECG, and heart sounds, especially during exercise (See Appendices G, H). Although intended to treat certain arrhythmias, this drug can unmask or precipitate new arrhythmias (proarrhythmic effect). Report any rhythm disturbances or symptoms of increased arrhythmias, including palpitations, chest pain, shortness of breath, fainting, and fatigue/weakness.
Watch for signs of congestive heart failure (CHF), including dyspnea, rales/crackles, peripheral edema, jugular venous distention, and exercise intolerance. Report these signs to the physician immediately.
Assess dizziness that might affect gait, balance, and other functional activities (See Appendix C). Report balance problems and functional limitations to the physician, and caution the patient and family/caregivers to guard against falls and trauma.
Because of the risk of CHF and serious cardiac arrhythmias, use extreme caution during aerobic exercise and other forms of therapeutic exercise. Assess exercise tolerance frequently (blood pressure, heart rate, fatigue levels), and terminate exercise immediately if any untoward responses occur (See Appendix L).
Advise patient and family/caregivers about the signs of CHF and cardiac arrhythmias (See above under Examination and Evaluation), and to seek immediate medical assistance if these signs develop.
Advise patient about the likelihood of GI reactions such as nausea, vomiting, constipation, stomach pain, and loss of appetite. Instruct patient to report severe or prolonged GI problems or signs of drug-induced hepatitis (yellow skin or eyes, abdominal pain, severe nausea and vomiting, fever, sore throat, malaise, weakness, facial edema).
Instruct patient and family/caregivers to report other side effects such as severe or prolonged headache, vision problems, tremor, fatigue, or skin rash.
Absorption: Well absorbed from the GI tract following oral administration.
Distribution: Widely distributed.
Metabolism and Excretion: Mostly metabolized by liver; 30% excreted unchanged by kidneys.
TIME/ACTION PROFILE (antiarrhythmic effects)
|ROUTE ||ONSET ||PEAK ||DURATION |
|PO ||days ||days–wks ||12 hr |