Care During Chemotherapy and Beyond

Hypocalcemia (Low Calcium)

What Is Hypocalcemia?

Hypocalcemia is an electrolyte imbalance and is indicated by a low level of calcium in the blood. The normal adult value for calcium is 4.5-5.5 mEq/L.

Calcium is important for healthy bones and teeth, as well as for normal muscle and nerve function. Normal blood calcium levels are maintained through the actions of parathyroid hormone (PTH), your kidneys and intestines.

If your blood test results show hypocalcemia, your doctor may check your albumin level as well. If your albumin is low, your calcium level should be corrected for this. A corrected calcium level will be higher if the albumin is low.

What Causes Hypocalcemia?

There are many causes of hypocalcemia, these include;

  • Vitamin D deficiency
  • Chronic renal failure
  • Magnesium deficiency
  • Alcoholism
  • Biphosphonate therapy - drugs used to treat high blood calcium levels or pills used to treat osteoporosis.
  • Certain types of leukemia or blood disorders
  • A complication of chemotherapy, tumor lysis syndrome, occurs when your body breaks down tumor cells rapidly, after chemotherapy. This may cause hypocalcemia, high blood potassium levels, and other electrolyte abnormalities. This is very serious, and if your blood test results indicate you suffer from it, your doctor or health care provider will need to closely monitor you during this time.
  • Drugs such as diuretics, estrogens replacement therapy, fluorides, glucose, insulin, excessive laxative use, and magnesium may also lead to hypocalcemia.
  • Certain things in your diet, like caffeine, phosphates (found in soda pop), and certain antibiotics may make it difficult for you to absorb calcium.
  • Vitamin D, however, helps you to absorb calcium in your body.

Symptoms of Hypocalcemia:

  • The most common sign of hypocalcemia is what is called "neuromuscular irritability." Your nerves and muscles, which are directly related to blood calcium levels, may spasm or twitch.
  • If your blood test results indicate hypocalcemia, you may notice muscle cramps in your legs or your arms.
  • The symptoms of hypocalcemia you experience may relate to how fast or how slowly the fall in blood calcium levels occur.
    • If you have long-standing low blood calcium levels, you may notice no symptoms of hypocalcemia.
    • If you have an "acute" or sudden drop in your blood calcium level, you may notice more twitching.
  • You may notice, with mildly lowered blood calcium levels, numbness and tingling of your fingers and toes.
  • You may notice that you are depressed, or more irritable if you have mildly low hypocalcemia.
  • With severely lowered blood calcium levels, you may become confused or disoriented. Your heart muscle may contract irregularly due to the electrolyte disturbance.

Things You Can Do For Hypocalcemia:

  • Make sure you take in enough calcium if your blood test results indicate hypocalcemia. The recommended intake of calcium daily, for bone health, is based on your age and race. If you are:
    • A man, age 25 to 65 years - take 1000 mg of calcium a day.
    • A man over the age of 65 years - take 1500 mg of calcium a day
    • A woman from age 25-50 - take 1000 - 1200 mg of calcium a day.
    • A woman over the age of 50 years - take 1500 mg of calcium a day.
  • Calcium, in any form, needs vitamin D to be absorbed. Take 400-800 mg of Vitamin D with your calcium supplements per day; to ensure that the calcium you take is being absorbed.
  • To increase your dietary intake of calcium, choose your foods wisely.
    • Greens (collard and kale)
    • sardines and salmon (with bones)
    • Red beans
    • seaweed
  • Dairy products contain the most calcium:
    • 8 oz. of milk or yogurt will provide 300 mg. of calcium.
    • 1 oz. of cheddar cheese will provide 200 mg of calcium.
    • 4 oz. of Tofu will give you 250 mg. of calcium.
  • Many cereals, orange juices, and other foods are fortified with calcium. Read the labels of your food items carefully.
  • If you do not take in enough calcium during hypocalcemia, especially if you have taken steroids for your disease that may cause "bone thinning," you are at risk for long term complications of bone loss (osteoporosis). You may be at a higher risk for fractures, curved spine, and loss of height.
  • Discuss with your healthcare provider if calcium replacement therapy is right for you.

Drugs That May Be Prescribed by Your Doctor:

  • As with all types of electrolyte imbalance, the treatment of hypocalcemia is based on correcting the cause. If there is a dysfunction of your endocrine or hormone system, you may be referred to an endocrinologist. If it is due to medications or treatments, these may be altered or removed, if possible.
  • For severely decreased levels a calcium infusion could be ordered.
  • Calcium pills or supplements. Follow instructions.
  • If you have mildly reduced blood calcium levels, increasing your dietary intake of calcium (see above) may be recommended.

When to Contact Your Doctor or Health Care Provider:

  • Severe constipation, unrelieved by laxatives, lasting 2 to 3 days.
  • Nausea that interferes with your ability to eat, and is unrelieved by any prescribed
  • Vomiting (vomiting more than 4-5 times in a 24 hour period).
  • Diarrhea (4-6 episodes in a 24-hour period), unrelieved with taking anti-diarrhea medication and diet modification.
  • Excessive sleepiness, confusion.
  • Muscle twitching or Irritability.
  • Increased urination.
  • Poor appetite that does not improve.

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