Concomitant administration of calcium-containing drugs may cause or aggravate elevated serum calcium levels.
Drugs that form hardly soluble compounds with calcium (e.g. tetracyclines, quinolones such as ciprofloxacin and norfloxacin as well as drugs containing iron, fluoride or estramustine) should not be taken at the same time with the products to avoid disturbed absorption of the active substances. An interval of at least two hours should elapse between the ingestion of the product and other drugs.
The susceptibility to cardioactive glycosides, and hence the risk for arrhythmia will increase if the product produces elevated serum calcium levels.
Uraemic symptoms improve under therapy with the product. Thus, in case of aluminum hydrochloride administration, the dose of these drugs has to be reduced if necessary. Serum phosphate levels should be monitored for a decrease.