Hypocalcemia foscarnet

Foscarnet Pentamidine IV Increased risk of severe nephrotoxicity/hypocalcemia Monitor renal functiorVserum calcium... 

Mineral and electrolyte imbalances Foscarnet has been associated with changes in serum electrolytes including hypocalcemia (15%), hypophosphatemia (8%) and hyperphosphatemia (6%), hypomagnesemia (15%), and hypokalemia (16%). Foscarnet is associated with a transient, dose-related decrease in ionized serum calcium, which may not be reflected in total serum calcium. 

Foscarnet should not be used in combination with drugs that cause renal toxicity (e.g., acyclovir, aminoglycosides, amphotericin B, NSAIDs). Abnormal renal function has been noted when foscarnet is used with ritonavir or ritonavir and saquinavir. Pentamidine may increase the risk of nephrotoxicity, hypocalcemia, and... 

Huycke MM, Naguib MT, Stroemmel MM, Blick K, Monti K, Martin-Munley S, Kaufman C. A double-blind placebo-con-troUed crossover trial of intravenous magnesium sulfate for foscarnet-induced ionized hypocalcemia and hypomagnesemia in patients with AIDS and cytomegalovirus infection. Antimicrob Agents Chemother 2000 44(8) 2143-8. 

Another previous report [187] described severe hypocalcemia with tetany in patients with AIDS concomitantly receiving pentamidine and foscarnet. The hypocalcemia, however, was attributed to the administration of foscarnet. Despite magnesium replacement, magnesium wasting may persist up to two months after the discontinuation of pentamidine, suggesting that anatomic renal tubular injury may be responsible [183,185]. Both abnormalities developed within 6 to 10 days of pentamidine administration. Because life-threatening arrhythmias can develop, especially at serum magnesium levels less than 1.6 mg/dl, early replacement therapy is clinically warranted. 

Youle MS,Clarbour J,Gazzard B,Chanas A. Severe hypocalcemia in AIDS patientstreated with foscarnet and pentamadine. Lancet 1988 1 1455-1456. 

Jacobson MA, Gambertoglio JG, Aweeka FT, Causey DM, Portale A. Foscarnet-induced hypocalcemia and effects of foscarnet on calcium metabolism. J Clin Endocrinol Metab 1991 72 1130-1135. 

Omar RF, Dusserre N, Desormeaux A, Poulin L, Tremblay M, Beauchamp D, Bergeron M. Liposomal encapsulation of foscarnet protects against hypocalcemia induced by free foscarnet. Antimicrob Agents Chemother 1995 39 1973-1978. 

Foscarnet 40-80 mg IV qShrs 85% 40-20 mg q8-24 hrs according to CICr Nephrotoxic, neurotoxic, hypocalcemia, hypophosphatemia, hypomagnesemia and hypokalemia... 

Clinical uses and toxicity The drug is used for prophylaxis and treatment of cytomegalovirus (CMV) infections (including CMV retinitis) and has activity against ganciclovir-resistant strains of this virus (Table 49-1). Foscarnet inhibits herpes DNA polymerase in acyclovir-resistant strains that are thymidine kinase-deficient and may suppress such resistant herpetic infections in patients with AIDS. Adverse effects include nephrotoxicity (30% incidence) with disturbances in electrolyte balance (especially hypocalcemia), genitourinary ulceration, and CNS effects (headache, hallucinations, seizures). 

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