Calcium is used as a pharmacologic agent in humans almost entirely to remedy deficiency. Adequate calcium in the blood is so vital to a wide variety of bodily functions that our internal biochemistry will not tolerate a deficiency even for short periods. Vitamin-C is an essential component of the diet as man can not synthesize vitamin-C. It is a very powerful reducing agent. Vitamin-C plays an important part in the response of the body to stress. It is important in the defense against infection.
Hypercalcemia (e.g. in hyperparathyroidism, vitamin-D overdosage, decalcifying tumors such as plasmocytoma, bone metastases); severe hypercalciuria; severe renal failure.
Patients with hyperoxalauria, glucose-6- phosphate dehydrogenase deficiency, or iron overload. Larger doses may lead to gastrointestinal tract upset.
In rare cases, mild gastrointestinal disturbances (bloating, diarrhea) can occur. In predisposed patients, prolonged treatment with high doses may promote the formation of calculi in the urinary tract.
Epidemiological studies with oral calcium have shown no increase in the teratogenic hazard to the fetus. Although supplemental calcium may be excreted in breast milk, the concentration is unlikely to be sufficient to produce any adverse effect on the neonate. Vitamin C may be taken safely during pregnancy and lactation.
For patients with mild hypercalciuria (exceeding 300 mg = 7.5 mmol/24 hours), with mild or moderate impairment of renal function or with a history of urinary concrements, monitoring of calcium excretion in the urine is required. If necessary, the dosage should be reduced or therapy should be discontinued. High doses of vitamin-D and derivatives should be avoided during treatment with this preparation unless especially indicated.
Since citrate salts have been reported to increase aluminium absorption, this medicine should be used with caution in patients with severely impaired renal function, especially those receiving aluminium-containing preparations. The sugar content should be taken into account by diabetic patients.
Acute overdosage has not been reported. It would be expected to cause gastrointestinal disturbances but not to result in hypercalcemia, except in patients treated with a very high dosage of vitamin-D and derivatives.