Zoledronic acid is used to treat and prevent osteoporosis. Learn how to use the medication, its common side effects, special precautions to watch out for, and more.

What is this medication for?

• Zoledronic acid belongs to a class of medication called “bisphosphonates”. They are used to treat and prevent osteoporosis – a condition which causes the bones to become weak and fragile. Bisphosphonates prevent bones from breaking down, hence, slowing down the process of osteoporosis.
• Zoledronic acid acid needs to be taken regularly for a long period of time to get its benefits. You should have an adequate intake of Calcium and Vitamin D (from food or supplements) to strengthen your bones. Calcium is the major building block of bone, and Vitamin D helps in the absorption of Calcium by the body.
  To reduce the risk of osteoporosis, you should engage in weight-bearing and muscle-strengthening exercises, stop smoking and consume alcohol in moderation. 

This leaflet will not address the use of Zoledronic acid, which is available in another strength (4mg), for the treatment of cancer-related bone conditions. The two strengths are not used interchangeably. 

How should I take or use this medication?

Zoledronic acid is administered as an infusion through a vein at a healthcare facility. Each infusion will take at least 15 minutes.

What should I do if I forget to take or use this medication?

If a dose is missed, reschedule your appointment with your clinic to administer as soon as possible. Thereafter, schedule doses every year from the date of last injection. 

What precautions should I take when taking or using this medication?

Inform your healthcare professional if: 

• You are allergic to this medication or any of the other ingredients of this medication.
• You are pregnant, planning to become pregnant, or breastfeeding
• You have any existing kidney problems

Ensure adequate hydration before administration of zoledronic acid.

Maintain good oral hygiene and go for regular dental check-ups. Your doctor may also require you to visit a dentist before starting on Zoledronic acid. Do Inform your dentist that you are taking Zoledronic acid.

What are some common side effects of this medication?

During the infusion, you may experience infusion reactions (fever with chills, joint pain and muscle ache). You may consider taking paracetamol 30 minutes before the infusion to prevent or reduce these side effects. If the symptoms persist, you may take another dose of Paracetamol 6 hours later. Other common side effects include nausea, tiredness, body aches and skin rashes

What are some rare but serious side-effects that I need to seek medical advice immediately?

These rare but serious side-effects generally occur in less than 5% of users who have osteoporosis and measures are taken to reduce the risk:

• You may experience passing less urine than usual or no urine, swelling in legs, ankles, and/or feet, tiredness, shortness of breath
• To reduce this risk, ensure adequate hydration before administration of zoledronic acid
• Due to low calcium levels, you may experience muscle cramps, numbness and tingling sensation in your lips or tongue, irregular heartbeat
  • Blood tests may be done to monitor your calcium levels
  • Ensure daily intake of calcium and vitamin D whilst undergoing treatment -these can be from dietary or supplement sources.
• Fast heartbeat, shortness of breath, chest discomfort, dizziness and/or fainting spells
• You may experience jaw pain, toothache, gum ulceration, delayed wound healing in mouth
  • You will be referred to a dentist to assess whether you can be started on zoledronic acid.
  • Ensure good oral hygiene and always inform your dentist that you are on this medication to avoid this rare but serious side effect.
• You may experience thigh or groin pain weeks or months with minimal or no injury to the area before the fracture occurs
  • You will be scheduled for bone scans every few years to assess the need to continue or temporarily stop zoledronic acid.
• Symptoms of a drug allergy include one or more of the following:
  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of the above symptoms, you should seek medical attention immediately.

How should I store this medication?

Store in a cool and dry place, away from direct sunlight. Keep this medication away from children. 

What else should I know about this medication?

You will be scheduled for bone scans every few years when on zoledronic acid. Depending on the results of the scan, your doctor may continue or stop zoledronic acid. If zoledronic acid is stopped, you will be scheduled for bone scans again to assess if you are required to restart treatment. 

Disclaimer

Please take note that the above is not a complete list of all possible side effects. If you have any concerns about your medication or if you have other side effects that you think are caused by this medication, please consult your doctor or pharmacist.

If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (National Healthcare Group, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.

Last updated July 2025