Calcitriol is used in the management of hypocalcaemia (low calcium level in the blood) and secondary hyperparathyroidism (high level of parathyroid hormone due to overactivity of parathyroid glands) in individuals undergoing long-term dialysis (a procedure to eliminate toxic substances from the blood).
Calcitriol injection is to be given intravenously (into the vein). It is delivered directly into the bloodstream via the blood vessel.
Your doctor or nurse will administer the injection for you.
The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on the severity of your condition and response to the medication.
Ensure that you keep all appointments with your doctor so that you do not miss any doses. Your doctor also needs to regularly monitor your response to Calcitriol.
If you miss an appointment or miss an injection, alert your doctor or nurse. A replacement appointment or injection should be given as soon as possible.
Alert your doctor if you have the following conditions:
- hypercalcaemia (high calcium level in the blood)
- abnormal calcium deposits in your body
- high level of vitamin D in your body
as Calcitriol may not be suitable for you.
Inform your doctor if you have the following conditions:
- malabsorption syndrome (inability of your intestines to absorb certain nutrients from the food you eat)
- immobility or have difficulty to move around e.g. after an operation or a surgery
- kidney disease
Let your doctor know if you are pregnant or breastfeeding.
Be sure to check with your doctor or pharmacist before giving Calcitriol to the elderly. Elderly people may be more sensitive to the side effects.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Routine tests (e.g. blood calcium, phosphorus, magnesium or parathyroid hormone levels; kidney function, urine calcium or phosphorus levels) may be done while you are being treated with this medicine.
- Regular monitoring for signs of high calcium level in the blood such as weakness, constipation, confusion and bone pain may also be needed.
Your doctor will advise you about how often you will need to have these tests.
Calcitriol may cause any of the following side effects: headache, drowsiness, nausea, vomiting, dry mouth, metallic taste, constipation, stomach pain, indigestion, decreased appetite, weight loss, muscle pain, numbness or tingling sensation in the hands and feet, and pain on the injection site.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- signs of high calcium levels in the blood e.g. weakness, confusion, constipation, bone pain, excessive thirst, irregular heartbeat, frequent urination
- rashes, breathlessness, swelling of the face, eyes or mouth
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- other medicines or supplements containing vitamin D
- water pills or medicines for water retention e.g. hydrochlorothiazide, bendroflumethiazide
- medicines for epilepsy (fits or seizures) e.g. phenytoin, phenobarbital, carbamazepine
- anti-inflammatory medicines e.g. prednisolone, dexamethasone, hydrocortisone
- medicines containing magnesium e.g. antacids
- colestyramine (cholesterol-lowering medicine)
- sevelamer (medicine used to lower phosphorus levels in the blood in individuals with long-term kidney disease)
- digoxin (medicine for heart disease)
- calcium supplements
This list does not include all medicines that may interact with Calcitriol.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Drink the appropriate amount of fluids daily to keep hydrated.
It is important that you have enough calcium in your body. It may be helpful to discuss your diet plan with your doctor or dietitian.
Avoid changing how much calcium or vitamin D you have in your diet, such as eating foods fortified with vitamin D, or eating more dairy products (e.g. milk, cheese) without informing your doctor.
It is important to adhere to the diet prescribed by your doctor.
Store in a cool, dry place away from the reach of children. Protect from light and moisture.
Medicines must not be used past the expiry date.