Calcium therapy adverse effects

Non-compliance is a serious problem in the prevention of osteoporosis and osteoporotic fractures. This is due to adverse effects, lack of noticeable benefit and ignorance. It is difficult to convince regular intake of oral calcium, biphosphonates, vitamin D and in post-menopausal women hormone replacement. Long-term compliance to hormone replacement is worse in developing countries. The most cost-effective therapy for osteoporosis is primary prevention. 

Gastrointestinal complaints (eg, nausea, diarrhea, vomiting, flatulence) are the most common adverse effects but rarely require discontinuation of therapy. Other potential adverse effects include headache and asthenia. Tenofbvir-associated proximal renal tubulopathy causes excessive renal phosphate and calcium losses and 1-hydroxylation defects of vitamin D, and preclinical studies in several animal species have demonstrated bone toxicity (eg, osteomalacia). Monitoring of bone mineral density should be considered with long-term use in those with risk factors for or with known osteoporosis, as well as in children. Reduction of renal function over time, as well as cases of acute renal failure and Fanconi s syndrome, have been reported in patients receiving tenofovir alone or in combination with emtricitabine. For this reason, tenofovir should be used with caution in patients at risk for renal dysfunction. Tenofovir may compete with other drugs that are actively secreted by the kidneys, such as cidofovir, acyclovir, and ganciclovir. 

CALCIUM CHANNEL BLOCKERS MACROLIDES t plasma concentrations of felodipine when co-administered with erythromycin cases of adverse effects of verapamil (bradycardia and 1 BP) with both erythromycin and clarithromycin Erythromycin inhibits CYP3A4-mediated metabolism of felodipine and verapamil. Clarithromycin and erythromycin inhibit intestinal P-gp, which may t the bioavailability of verapamil Monitor PR and BP closely watch for bradycardia and 1 BP. Consider reducing the dose of calcium channel blocker during macrolide therapy... 

Throbbing headache, facial warmth and flushing, and dizziness are minor complaints associated with the use of calcium channel blockers these effects are beheved to be caused by inhibitory actions on smooth muscle (20). Palpitation, muscle cramps, and pedal edema also occur (21-27). Dizziness, facial flushing, leg edema, postural hypotension, and constipation have been reported in up to one-third of patients. They are rarely severe and often abate on continued therapy. More serious adverse effects, mainly those affecting cardiac conduction, are much less common, and only rarely is withdrawal necessary. 

Reduced folates are co-factors for the 5-fluorodeoxy-uridine monophosphate-thymidilate synthetase reaction. Leucovorin (calcium fohnate) therefore potentiates the toxicity of 5-fluorouracil, and fatal adverse effects have been reported in patients over 65 years of age receiving high-dose treatment with leucovorin simultaneously with fluorouracil. This has led some groups to recommend that initial dose levels of fluorouracil should be lowered by 20% and that therapy be stopped temporarily at the first sign of distal gastrointestinal adverse effects (SEDA-15, 414). 

The possibility that calcium channel blockers can cause cardiovascular adverse effects in pregnancy has been widely debated (SED-14, 598) (SEDA-20, 185) (SEDA-21, 208) (SEDA-22, 214). An uncomplicated non-Q wave myocardial infarction has been reported during nifedipine therapy for preterm labor (43). 

Women receive the same benefits from antihypertensive therapy as men. However, ACE inhibitors and ARBs are contraindicated in women who intend to become pregnant because they are teratogenic. Thiazide diuretics may be especially beneficial in postmenopausal women with osteoporosis because they cause retention of calcium and have been shown to positively affect bone mineral density. Women tend to have higher rates of drug-related adverse effects than men. 

Once patients with angina develop symptoms sufficient for pharmacologic therapy on a daily basis, the initial prophylactic therapy recommended is a /3-blocker. There is a paucity of comparative, long-term clinical trials of 8-blockade versus calcium channel blockers to determine which is superior for survival benefit. /3-Blockers are recommended first-line therapy because of theirefficacy in post-MI patients and favorable adverse-effect profile. 

Mithramycin (plicamycin) is a potent cytotoxic antibiotic that inhibits osteoclast-mediated bone resorption and thereby reduces hypercalcemia. Mithramycin may be administered at a dose of 25 mcg/kg via intravenous infusion over 4 to 6 hours in saline or 5% dextrose solutions. This therapy may be repeated daily for 3 to 4 days or on alternating days for 3 to 8 doses. ° Serum calcium levels begin to fall within 12 hours of a mithramycin dose, with the peak effect generally occurring within 48 to 96 hours.Single doses are usually well tolerated. Adverse effects of mithramycin include nausea, vomiting, stomatitis, thrombocytopenia, inhibition of platelet function, and renal and hepatotoxicity. Because these adverse effects are more commonly associated with multiple doses, mithramycin is usually limited to short-term therapy in patients who have not responded to alternative therapies. Monitoring parameters include complete blood count, liver function, and renal function. Mithramycin should be avoided in patients with thrombocytopenia and liver and renal insufficiency. ... 

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