All are toxicities seen with Amiodarone therapy except aEUR'
Productive cough Amiodarone is a class III antiarryhthmic drug and thus blocks potassium channel. It acts by increasing the action potential duration and effective refractory period. In spite of its present classification as class 3 drug, amiodarone also significantly blocks inactivated sodium channels. It also has weak adrenergic and calcium channel blocking actions. Consequence of these actions include slowing of the hea rate and AV node conduction. Amiodarone is the most powerful antiarryhthmic drug available for the treatment and prevention of both atrial and ventricular anyhthmias. Adverse effect :? Even sho term use of Amiodarone causes serious toxicity. Amiodarone accumulates in many tissues which includes hea, lung, liver and skin. Pulmonary toxicity It is the most impoant adverse effect. It is dose related. Fatal pulmonary fibrosis may be observed even in low doses. Patient usually presents with cough, chest pain and shoness of breath. Symptoms usually sta with dry cough and dvspnoea. Remember, that patients on amiodarone often have dypnoea attributable to other problems such as hea failure, so amiodarone lung toxicity is difficult to diagnose. Liver toxicity Abnormal liver function and hepatitis develops during amiodarone therapy. (1 have not got any documented evidence Oliver cirrhosis). Skin deposits Skin deposits results in photoderrnatitis and gray blue skin discoloration in sun exposed areas e.g. the malar region. Corneal microdeposits Corneal microdeposits are seen in viually all patients treated with Amiodarone after few weeks of treatment. Sometimes optic neuritis may develop and progress to blindness. Effect of Amiodarone on Thyroid Amiodarone is a potential source of large amount of inorganic iodine and it also blocks the peripheral conversion of thyroxine (T4) to triiodothyronine (T3). Thus Amiodarone may result in hypothyroidism or hypehyroidism. Thyroid function should be evaluated prior to initiation of treatment and monitored periodically. Cardiac toxicity Amiodarone may produce symptomatic bradycardia and hea block in patients with preexisting sinus or A-V node disease.
Pulmonary fibrosis
Corneal micro-deposits
Cirrhosis of liver
Productive cough