Cholecalciferol/lutein/omega-3 polyunsaturated fatty acids/zeaxanthin Disease Interactions

Vitamin D analogs function to increase serum calcium concentrations and can exacerbate arrhythmias, particularly in patients receiving cardiac glycosides. Therapy with vitamin D analogs should be administered cautiously in patients with or predisposed to cardiac arrhythmias. Clinical monitoring of serum electrolyte concentrations and cardiac function is recommended.

Vitamin D analogs administered in the presence of hyperphosphatemia can result in precipitation of calcium-phosphate deposits within the vascular or renal systems or other soft tissue calcifications. A solubility product (Serum Calcium X Phosphate) should not exceed 70. Serum electrolyte concentrations should be corrected prior to vitamin D analog therapy and monitored during therapy.

Vitamin D analogs such as calciferol and ergocalciferol should not be given to patients with hypercalcemia, malabsorption syndrome, or evidence of vitamin D toxicity.

Ergocalciferol, cholecalciferol, and calcifediol undergo renal biotransformation during metabolic activation. Renal impairment can alter metabolic and therapeutic activity of certain vitamin D analogs. Alternative vitamin D analogs such as dihydrotachysterol (hepatic activation) and calcitriol (active form) may be considered in patients with compromised renal function.

Cases of recurrent atrial fibrillation (AF) or flutter have been reported with the use of omega-3 fatty acids in patients with a symptomatic paroxysmal AF or persistent AF. This condition is more apparent within the first 2 to 3 months after the initiation of therapy. Therapy with these agents should be administered cautiously in patients with cardiac conduction disorders.

Increases in alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) levels have been observed in patients receiving omega-3 fatty acids. Therapy with omega-3 fatty acid preparations should be administered cautiously in patients with hepatic impairment. Serum liver enzyme levels should be monitored periodically.

Vitamin D analogs are fat soluble and oral formulations require bile for adequate intestinal absorption. Hepatic and/or biliary dysfunction decrease the absorption of vitamin D analogs. Metabolites of vitamin D analogs are primarily excreted in bile and feces. Ergocalciferol, cholecalciferol, and dihydrotachysterol undergo hepatic hydroxylation during metabolic activation. Hepatic impairment can alter the metabolic and therapeutic activity of certain vitamin D analogs. Alternative vitamin D analogs such as calcifediol (requires renal activation) and calcitriol (active form) may be considered in patients with compromised hepatic function.