Teriparatide
Also known as: Forteo · Terrosa · Parathyroid hormone (1-34)
When slowing bone loss may not be enough. Most osteoporosis medicines work mainly by slowing bone breakdown. Teriparatide works differently, because it stimulates the body to build new bone. I consider it for people with severe osteoporosis or a very high risk of another fracture, usually as part of a carefully planned treatment sequence.
Calm, careful medication review by a consultant rheumatologist.
What this medicine is
Teriparatide is an anabolic, or bone-building, osteoporosis medicine. It is a manufactured version of the active part of parathyroid hormone, the natural hormone involved in regulating calcium and bone metabolism. Given as a small injection under the skin once a day, it encourages the cells that build bone to become more active, which over time can improve bone density and reduce the risk of certain osteoporotic fractures. In simple terms, antiresorptive medicines slow bone breakdown, while teriparatide stimulates new bone formation. It is not a painkiller and it does not give immediate relief from back or joint pain.
Uses and context
I generally reserve teriparatide for people with severe osteoporosis or a very high risk of fracture. That may include multiple fractures from minor falls or everyday movements, one or more spinal compression fractures, a recent osteoporotic fracture, very low bone mineral density, a fracture despite taking treatment correctly, continued bone loss on treatment, side effects that prevent other medicines being used, osteoporosis linked to long-term steroid treatment, or a combination of advanced age, frailty and high falls risk. The Malaysian osteoporosis guideline recommends considering anabolic treatment for very-high-risk patients, particularly those with multiple vertebral fractures or osteoporosis that has not responded well enough to other treatment.
How this relates to rheumatology care
Teriparatide is usually given as a 20 microgram injection once daily with a prefilled pen, into the skin of the thigh or abdomen, and I teach you or your caregiver how to give it safely. The Malaysian Clinical Practice Guidelines recommend up to 24 months of treatment, so it is a limited course rather than a lifelong daily injection. What happens afterwards matters just as much. Once the course is complete I normally prescribe an antiresorptive medicine such as a bisphosphonate or denosumab, because without follow-on treatment some of the bone density gained can be lost. The sequence I plan for is: build bone with teriparatide, complete the planned course, continue with an antiresorptive medicine, then maintain bone strength and fracture protection. Alongside the injection I also review calcium and vitamin D intake, weight-bearing and resistance exercise, balance training, falls prevention, protein intake, smoking and alcohol, and any medicines that increase falls or weaken bone.
What safety checks may matter
Bone mineral density scan and full fracture history
Calcium and vitamin D levels, corrected before starting if needed
Kidney function and blood tests for secondary causes of osteoporosis
Current and previous osteoporosis medicines, and how you responded
History of kidney stones, cancer or radiotherapy involving the skeleton
Other medicines you take, including digoxin
Injection technique, missed doses and side effects reviewed at follow-up
Repeat bone density testing at intervals I decide with you, commonly every one to three years in high-risk patients
Side effects and red flags
If you have emergency symptoms such as severe allergic reaction, breathing difficulty, chest pain, stroke-like symptoms, severe abdominal pain, vomiting blood, black stools, sudden vision loss, severe infection symptoms, or severe weakness or confusion, please seek urgent medical care first rather than waiting for a WhatsApp reply.
Persistent nausea or vomiting
Marked muscle weakness or severe constipation
Unusual tiredness, confusion or ongoing dizziness
Palpitations
Symptoms of a kidney stone
A significant allergic reaction
New or unexplained persistent bone pain
Things worth knowing day to day
Take the injection at about the same time each day, rotate the injection site and use a new needle each time.
Never share the injection pen, even with a new needle.
Store the pen as instructed for your specific brand and do not use it if it has been frozen. Dispose of needles in a sharps container.
Take the first few doses where you can sit or lie down, as temporary light-headedness can occur.
If you miss a dose, do not inject two doses together. Continue with the next scheduled dose.
Common side effects include nausea, dizziness, leg cramps, joint or body pain, headache, injection-site discomfort and a temporary rise in blood calcium.
It is generally avoided in high blood calcium, primary hyperparathyroidism, Paget's disease of bone, cancer spread to bone, previous skeletal radiation, inherited osteosarcoma risk, growing bones, pregnancy and breastfeeding.
Do not stop treatment without a follow-on osteoporosis plan agreed with me first.
Questions patients often ask me about this medicine
Speak with me
Osteoporosis can stay silent until a bone breaks, and after one fragility fracture preventing the next one becomes especially important. If you have severe osteoporosis or have already had a fracture, please message my clinic so I can assess whether teriparatide, another bone-building medicine or an antiresorptive treatment is the right next step for you.
Trusted patient information sources
Other medications used in rheumatology care
This page is for general education only and does not replace medical advice. Please consult a qualified healthcare professional for diagnosis and treatment. Do not start, stop, or change any medicine without advice from your doctor.