AHFS/Drugs.com Monograph CAS Number 299-28-5 | Routes of
administration by mouth, IV, topical | |
 | ||
Pronunciation KAL see um GLUE koe nate Pregnancy
category US: A (No risk in human studies) and C ATC code A12AA03 (WHO) D11AX03 (WHO) | ||
Calcium gluconate is a mineral supplement and medication. As a medication it is used by injection into a vein to treat low blood calcium, high blood potassium, and magnesium toxicity. Supplementation is generally only required when there is not enough calcium in the diet. Supplementation may be done to treat or prevent osteoporosis or rickets. It can also be taken by mouth but is not recommended by injection into a muscle.
Contents
- Low blood calcium
- High blood potassium
- Magnesium sulfate overdose
- Hydrofluoric acid burns
- Black widow spider bites
- Cardiac arrest
- Side effects
- Society and culture
- References
Side effects when injected include slow heart rate, pain at the site of injection, and low blood pressure. When taken by mouth side effects may include constipation and nausea. Blood calcium levels should be measured when used and extra care should be taken in those with a history of kidney stones. At normal doses use is regarded as safe in pregnancy and breastfeeding. Calcium gluconate is manufactured by mixing gluconic acid with calcium carbonate or calcium hydroxide.
Calcium gluconate came into medical use in the 1920s. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. Calcium gluconate is avaliable as a generic medication. The wholesale cost in the developing world is about 0.21 to 1.34 USD per one gram vial, 10 ml of 100 mg/ml (10% solution). In the United Kingdom this amount costs the NHS about 0.65 pounds.
Low blood calcium
10% calcium gluconate solution (given intravenously) is the form of calcium most widely used in the treatment of low blood calcium. This form of calcium is not as well absorbed as calcium lactate, and it only contains 0.93% (930 mg/dl) calcium ion (defined by 1 g weight solute dissolved in 100 ml solvent to make 1% solution w/v). Therefore, if the hypocalcaemia is acute and severe, calcium chloride is given instead.
High blood potassium
Calcium gluconate is used as a cardioprotective agent in high blood potassium, with one alternative being use of calcium chloride. It is recommended with the potassium levels are high (>6.5 mmol/l) or there are changes of high blood potassium on the electrocardiogram (ECG).
Though it does not have an effect on potassium levels in the blood, it reduces the excitability of cardiomyocytes thus lowering the likelihood of developing cardiac arrhythmias.
Magnesium sulfate overdose
It is also used to counteract an overdose of Epsom Salts magnesium sulfate, which is often administered to pregnant women in order to prophylactically prevent seizures (as in a patient experiencing preeclampsia). Magnesium sulfate is no longer given to pregnant women who are experiencing premature labor in order to slow or stop their contractions (other tocolytics are now used instead due to better efficacy and side effect profiles). Excess magnesium sulfate results in magnesium sulfate toxicity, which results in both respiratory depression and a loss of deep tendon reflexes (hyporeflexia). Calcium gluconate is the antidote for magnesium sulfate toxicity.
Hydrofluoric acid burns
Gel preparations of calcium gluconate are used to treat hydrofluoric acid burns. This is because calcium gluconate reacts with hydrofluoric acid to form insoluble, non-toxic calcium fluoride.
Black widow spider bites
Historically, IV calcium gluconate was used as an antidote for black widow spider envenomation, often in conjunction with muscle relaxants. This therapy, however, has since been shown to be ineffective.
Cardiac arrest
While intravenous calcium has been used in cardiac arrest its general use in not recommended. Cases of cardiac arrest in which it is still recommended include high blood potassium, low blood calcium such as may occur following blood transfusions, and calcium channel blocker overdose. There is the potential that general use could worsen outcomes. If calcium is used calcium chloride is generally the recommended form.
Side effects
Calcium gluconate side effects include nausea, constipation, upset stomach. Rapid intravenous injections of calcium gluconate may cause hypercalcaemia, which can result in vasodilation, cardiac arrhythmias, decreased blood pressure, and bradycardia. Extravasation of calcium gluconate can lead to cellulitis. Intramuscular injections may lead to local necrosis and abscess formation.
It is also reported that this form of calcium increases renal plasma flow, diuresis, natriuresis, glomerular filtration rate, and prostaglandin E2 and F1-alpha levels.
Society and culture
Shortages of medical calcium gluconate were reported in November 2012 and November 2015 in the United States.