What is denosumab and how is it taken?

Denosumab works by blocking a protein called RANK ligand, which occurs naturally in the body. Blocking this protein limits the activity of cells (osteoclasts) that break down old bone material. It therefore helps to increase bone mass and strength.

Denosumab is recommended for osteoporosis in:

  • postmenopausal women who can't take bisphosphonates
  • men who have developed osteoporosis as a result of treatment for prostate cancer.

Denosumab is given as an injection under the skin (subcutaneously) twice a year.

Side-effects and risks

Common possible side-effects include:

  • occasional skin infections (cellulitis) at the site of the injection
  • back pain
  • arm and leg pain
  • urinary tract infections
  • constipation
  • rash.

Less common side-effects include:

  • low blood calcium – your blood levels will be checked before you start treatment

and, rarely:

  • osteonecrosis of the jaw – a condition where healing is incomplete following an invasive dental procedure. An area of bone is exposed through the gum and a small amount of bone dies. This condition is more common if you have cancer, are having chemotherapy or you have severe, recurrent dental infections and are having dental treatment.
  • painful, partial or complete fractures in the upper, outer region of the thigh bone (femur) below the hip. Partial fractures are usually confirmed by a special diagnostic scan. The risk appears to increase the longer you've been taking these drugs, and may be greater if you're also having steroid treatment or have diabetes. However, it's still extremely rare.

Effects on other treatments

It's usually fine to take other medicines alongside denosumab, but check with your doctor or pharmacist before starting any new medications.

There's no reason why you shouldn't have vaccinations while you're on denosumab.


Alcohol is unlikely to interact with denosumab. However, heavy drinking is a risk factor for osteoporosis and for having falls so it's recommended that you drink alcohol only in moderation.

Fertility, pregnancy and breastfeeding

Denosumab isn't normally recommended for women of child-bearing age. It's recommended that it should not be used by women who are pregnant, planning to become pregnant or breastfeeding.

What else should I know?

Calcium and vitamin D

It's important to get enough calcium and vitamin D. You may be prescribed a daily supplement of calcium and/or vitamin D if your doctor thinks you may have a deficiency.