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Reclast: 7 things you should know

Medically reviewed by Carmen Fookes, BPharm. Last updated on Jan 3, 2023.

1. How it works

  • Reclast is a brand (trade) name for zoledronic acid which may be used to strengthen bones and to treat or prevent osteoporosis.
  • Reclast (zoledronic acid) works by inhibiting osteoclasts which are responsible for breaking down and reabsorbing bone (by a process known as bone resorption). It also inhibits increased osteoclastic activity and the release of calcium by the skeleton induced by tumors.
  • Reclast belongs to the class of medicines known as bisphosphonates.

2. Upsides

  • Reclast may be used to treat or prevent osteoporosis caused by menopause, steroid use, or low hormone levels due to gonadal failure.
  • Reclast may also be used to increase bone mineral density in men and to treat Paget's disease of the bone in men and women.
  • Reclast only requires administration every year for the treatment of osteoporosis, and every two years for the prevention of osteoporosis.
  • Reclast is available as a generic under the name zoledronic acid.

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Fever, nausea, constipation, anemia, and shortness of breath are the most frequently reported side effects. Low blood pressure, abdominal pain, and vomiting may also occur.
  • A lowering in the levels of certain electrolytes such as phosphate, potassium, and magnesium may occur.
  • Some people report insomnia, anxiety or confusion, coughing, and skeletal pain with Reclast.
  • The optimal duration of use of Reclast has not been determined. Discontinuation of therapy should be considered by doctors after 3 to 5 years in patients with osteoporosis who have a low risk of fracture. Patients who discontinue therapy should have their risk for fracture re-evaluated periodically.
  • May not be suitable for some people including those with kidney disease, pre-existing esophageal or gastrointestinal conditions, low blood calcium levels (hypocalcemia), or dental disease. Rare reports of bronchoconstriction (a narrowing of the airways) have been reported in aspirin-sensitive patients given Reclast.
  • There are concerns about the long-term safety of bisphosphonates (such as Reclast) as long-term use has been associated with atypical femur fractures, osteonecrosis of the jaw, and esophageal cancer. The risk of osteonecrosis of the jaw is greater in those who have received chemotherapy, radiation, or steroids.
  • Rarely may cause other side effects including uveitis (eye inflammation) and other adverse effects. Severe and occasionally incapacitating bone joint or muscle pain has also been reported. Reclast should be discontinued if this occurs.
  • May interact with some other medicines such as aminoglycosides or calcitonin (may have an additive calcium-lowering effect), loop diuretics (an additive sodium-lowering effect) as well as other drugs that may also adversely affect the kidneys. Reclast should never be given at the same time as other bisphosphonates, such as Zometa.
  • Reclast is only available as an injection for administration by a healthcare provider.
  • Reclast must be administered over no faster than 15 minutes because shorter infusion times have been associated with an increased risk of renal toxicity which may progress to kidney failure.
  • Avoid during pregnancy. Bisphosphonates, such as Reclast, can cause fetal harm in animals, such as renal pelvis ureter syndrome and interference with natural delivery. Animal data suggest that the uptake of bisphosphonates into fetal bone is greater than into maternal bone. There are no data on fetal risk and pregnancy in humans. It is unknown if Reclast is excreted into human milk and use should be avoided.

Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects

4. Bottom Line

  • Reclast may be used to treat or prevent osteoporosis caused by menopause, steroid use, or gonadal failure, in the treatment of Paget's disease, and to increase bone mineral density in men. Reclast only requires administration every year for the treatment of osteoporosis, and every two years for the prevention of osteoporosis.

5. Tips

  • You may need to take supplementary calcium or vitamin D if your dietary intake is inadequate. Your doctor will advise you about this.
  • Tell your doctor if you have ever had kidney problems in the past before taking Reclast.
  • Make sure you get your laboratory tests done (which includes a test for creatinine) during your Reclast therapy.
  • Make sure you have a dental check-up before you start Reclast. Talk to both your dentist and doctor if you require dental surgery or tooth extraction and you have been administered Reclast. Keep good oral hygiene and get regular dental check-ups while you are being given Reclast. Report any oral symptoms such as tooth pain, jaw pain, loose teeth, or mouth ulcers to your doctor while you are being administered Reclast.
  • Tell your doctor if you experience any thigh or groin pain, muscle cramps or twitches, severe or debilitating muscle pain, eye inflammation, or any other adverse effects of concern while you are being administered Reclast.
  • Do not take any other medications with Reclast without first talking with your doctor. Never take other bisphosphonates (such as Zometa) while taking Reclast.
  • Tell your doctor if you are sensitive to aspirin before you are administered Reclast. Report any feelings of breathlessness to your doctor if they occur while taking Reclast.
  • Do not take Reclast while pregnant or breastfeeding. If you inadvertently become pregnant while being administered Reclast, tell your doctor immediately.

6. Response and effectiveness

  • The effectiveness of Reclast is comparable to most other bisphosphonates; however, because it has a very favorable dosing regimen, people prefer it because it does not have to be taken as often as some other bisphosphates.
  • After treatment with Reclast, BMD increased by 11% from baseline after one year of treatment and by 20.7% from baseline after two years of treatment.

7. Interactions

Medicines that interact with Reclast may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with Reclast. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with Reclast include:

  • aminoglycoside antibiotics, such as amikacin, gentamicin, kanamycin, neomycin, paromomycin, or tobramycin
  • angiogenesis inhibitors, such as bevacizumab or everolimus
  • aspirin
  • calcitonin
  • deferasirox
  • diuretics, such as bumetanide, ethacrynic acid, or furosemide
  • digoxin
  • chemotherapy agents for cancer
  • NSAIDs, such as ibuprofen, diclofenac, and naproxen
  • oral steroids, such as dexamethasone, prednisone, and methylprednisone
  • proton pump inhibitors, such as omeprazole
  • thalidomide.

Note that this list is not all-inclusive and includes only common medications that may interact with Reclast, You should refer to the prescribing information for Reclast for a complete list of interactions.


Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Reclast only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2023 Revision date: January 3, 2023.