General
Excessive dosage of PhosLo induces hypercalcemia; therefore,
early in the treatment during dosage adjustment serum calcium should be
determined twice weekly. Should hypercalcemia develop, the dosage should be
reduced or the treatment discontinued immediately depending on the severity of
hypercalcemia. PhosLo should not be given to patients on digitalis, because
hypercalcemia may precipitate cardiac arrhythmias. PhosLo therapy should always
be started at low dose and should not be increased without careful monitoring of
serum calcium. An estimate of daily calcium intake should be made initially and
the intake adjusted as needed. Serum phosphorus should also be determined
periodically.
Information for the Patient
The patient should be informed about compliance with dosage
instructions, adherence to instructions about diet and avoidance of the use of
nonprescription antacids. Patients should be informed about the symptoms of
hypercalcemia (see ADVERSE REACTIONS section).
Drug Interactions
PhosLo may decrease the bioavailability of tetracyclines.
Carcinogenesis, Mutagenesis, Impairment of
Fertility
Long term animal studies have not been performed to evaluate the
carcinogenic potential, mutagenicity, or effect on fertility of PhosLo.
Pregnancy
Teratogenic Effects: Category C. Animal reproduction studies have
not been conducted with PhosLo. It is not known whether PhosLo can cause fetal
harm when administered to a pregnant woman or can affect reproduction capacity.
PhosLo should be given to a pregnant woman only if clearly needed.
Pediatric Use
Safety and effectiveness in pediatric patients have not been
established.
Geriatric Use
Of the total number of subjects in clinical studies of PhosLo
(n=91), 25 percent were 65 and over, while 7 percent were 75 and over. No
overall differences in safety or effectiveness were observed between these
subjects and younger subjects, and other reported clinical experience has not
identified differences in responses between the elderly and younger patients,
but greater sensitivity of some older individuals cannot be ruled out.