The simultaneous administration of medicaments containing calcium (e.g., acetolyte) may lead to pathological increase of the serum calcium level or intensification. As the uraemic symptoms improve under Ketoanalogues + Essential amino acids, a possible administration of aluminum hydroxide should be reduced. Pay attention to a reduction of serum phosphate. In order not to interfere with absorption, do not take Ketoanalogues + Essential amino acids together with drugs that form sparingly soluble compounds with calcium [e.g., tetracyclines, quinolone (e.g., ciprofloxacin, norfloxacin), iron, fluoride, and estramustine-containing drugs]. Between the intake of Ketoanalogues + Essential amino acids and drugs from the mentioned categories, a period of at least 2 hours should pass. The susceptibility towards heart/cardiac-active glycosides and hence also the risk of arrhythmia increase with the rise of the blood calcium concentration.