Paricalcitol

Paricalcitol

Paricalcitol is a type of medicine called vitamin D analog. This is used to treat overactivity of the parathyroid glands in people with chronic kidney failure. A high level of parathyroid hormone is caused by a low level of calcium and a certain kind of vitamin D. Too much parathyroid hormone can cause serious problems. Paricalcitol helps reduce parathyroid hormone levels and may help your body absorb calcium and phosphorus. 

Overactive parathyroid gland

This happens when your parathyroid glands make too much parathyroid hormone in the bloodstream. These glands are located behind the thyroid at the bottom of your neck. The parathyroid glands produce parathyroid hormone. This hormone helps maintain an appropriate balance of calcium in the bloodstream and in tissues that depend on calcium for proper functioning. This condition is often diagnosed before signs or symptoms of the disorder are apparent. When symptoms do occur, they are the result of damage in other organs or tissues. Symptoms may be so mild and nonspecific that they don’t seem related to parathyroid function. The range of signs and symptoms may include:

  • Kidney stones
  • Osteoporosis 
  • Abdominal pain
  • Excessive urination
  • Bone and joint pain
  • Tiring easily or weakness
  • Nausea
  • Loss of appetite
  • Vomiting
  • Frequent complaints of illness with no apparent cause 

Chronic kidney failure

This describes the gradual loss of kidney function. Your kidneys filter wastes and excess fluids from your blood which are then excreted in your urine. When the chronic disease reaches an advanced stage, dangerous levels of fluid, electrolytes, and wastes can build up in your body. Signs and symptoms of this condition may develop over time if kidney damage progresses slowly. Signs and symptoms of kidney disease may include:

  • Vomiting
  • Nausea
  • Fatigue and weakness
  • Loss of appetite
  • Sleep problems
  • Decreased mental sharpness
  • Changes in how much you urinate
  • Persistent itching
  • Swelling of feet and ankles 
  • Muscle twitches and cramps 

Diseases/conditions that cause chronic kidney failure are:

  • High blood pressure
  • Type 1 or type 2 diabetes
  • Polycystic kidney disease
  • Interstitial nephritis
  • Recurrent kidney function

How does Paricalcitol work?

In chronic kidney failure, the parathyroid glands can become overactive. This is because in kidney failure the level of calcium in the blood can fall too low. The level of calcium in the blood is closely related to the activity of vitamin D in the body. The kidneys normally convert vitamin D into an active form called calcitriol. This helps control the absorption of calcium from the gut and its turnover in the bone. However, in chronic kidney failure, the kidneys are less effective at converting vitamin D into calcitriol. As a result, less calcium is absorbed from the gut which causes the level of calcium in the blood to drop. The parathyroid glands produce more parathyroid hormone in response to this. Wherein, it causes more calcium to be reabsorbed from the bone. This can weaken the bone and result in a condition called renal osteodystrophy.

Paricalcitol is a synthetic form of calcitriol. It works by binding to two specific receptors on the parathyroid glands known as vitamin D receptors and calcium-sensing receptors. By binding to these two receptors, Paricalcitol decreases the production and release of parathyroid hormone from the parathyroid glands. This helps to control levels of calcium and phosphate in the body. It plays an important part in the regulation of bone mineralization in people with chronic kidney failure.

How to use Paricalcitol?

Paricalcitol is taken usually once a day or 3 times a week or as directed by your doctor. Each dose is taken by mouth with or without food. Do not take this medicine more often than every other day. 

Follow your doctor’s orders. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so. The amount of medicine that you take depends on the strength of the medicine. Similarly, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

To help you remember, take it at the same time each day. if you are taking this medication on a schedule other than every day, it may help to mark your calendar with a reminder. It is very important to follow the diet recommended by your doctor to get the most benefit from it. Tell your doctor at once if your condition does not improve or gets worse. 

What are the side effects of Paricalcitol?

  • Dizziness
  • Headache
  • Cough
  • Lower back or side pain
  • Skin rash 
  • Painful or difficult urination
  • Nervousness
  • Unusual tiredness or weakness
  • Abdominal pain
  • Bloating
  • Bladder pain
  • Anxiety
  • Cold sweats
  • Bloody or cloudy urine
  • Loss of appetite
  • Nausea
  • Vomiting
  • Shakiness
  • Sore throat
  • Weight loss
  • Troubled breathing
  • Wrinkled skin
  • Sore throat
  • Stabbing pain
  • Sneezing
  • Slurred speech
  • Hoarseness
  • Puffiness or swelling of the eyelids or around the face, eyes, tongue, or lips 

Warnings:

  • While having treatment with this medication, you should have regular blood tests to monitor the levels of phosphate, calcium, and parathyroid hormone in your blood. 
  • Paricalcitol contains ethanol which may be harmful to people suffering from alcoholism, epilepsy, or liver disease. 
  • Consult your doctor first if you are using this in children under 5 years of age and limited experience in children over 5 years of age. 
  • This medication should be used with caution in elderly people, severely decreased liver function, and people taking digoxin. 
  • This drug should not be given in people with high levels of calcium in the blood and with too much vitamin D in the body. 
  • Paricalcitol may not be recommended for use in pregnant or breastfeeding women unless it is needed. If you are planning to become pregnant, tell your doctor beforehand. 
  • If you are allergic to any of the ingredients of this drug, you should not take any dose of it. Inform your doctor if you have any allergies. 
  • Tell your doctor about the medications you are taking. It may include herbal products, food supplements, or vitamins.