Digoxin serum concentration monitoring

To evaluate effectiveness of serum digoxin concentration monitoring, and determine cost impact of service OD None None NOI, timing of digoxin serum concentrations, laboratory costs avoided Decreased number of digoxin serum drug concentrations ordered Input costs not considered... 

When azithromycin is used concomitantly with digoxin, serum digoxin concentrations need to be monitored (47). While data on the effects of azithromycin on the intestinal metabolism of digoxin have not been reported so far, it is likely that it will affect Eubacterium lentum, like other macrolides. 

If conversion to normal sinus rhythm has not been achieved by the second day of treatment, digoxin may be coadministered p.o. at 0.011 mg/ kg twice daily. This offsets the proarrhythmic effect of quinidine by slowing conduction through the AV node. However, coadministration of digoxin and quinidine will affect serum concentrations of each drug and, therefore, serum digoxin concentration should be monitored if its... 

Klamerus, K.J. Munger, M.A. Effect of clinical pharmacy services on appropriateness of serum digoxin concentration monitoring. Am. J. Hosp. Pharm. 1988, 45, 1887-1893. 

A very well established interaetion of clinical importance. Monitor the ef-feets ofeoneurrent use and reduce the digoxin dosage appropriately in order to avoid toxieity. Most patients appear to be affected and dosage reductions in the range 15 to 70% were found necessary in one of the studies cited. The data available suggest that the extent of the rise may possibly depend on the propafenone serum concentration rather than on its dose. ... 

Calcium channel blockers interact with cardiac glycosides. The main mechanism is inhibition of digoxin renal tubular secretion by inhibition of P glycoprotein. In a review of the interactions of calcium channel blockers with digoxin, in which their clinical relevance was assessed, it was concluded that serious consequences can be prevented by careful monitoring, especially in patients whose serum digoxin concentration is already near the upper end of the therapeutic range (174). 

Wahed A, Dasgupta A. Positive and negative in vitro interference of Chinese medicine dan shen in serum digoxin measurement elimination of interference by monitoring free digoxin concentration. Am J Clin Pathol 2001 116 403-408. 

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