Common Side Effects of Forteo
Forteo (teriparatide), used to treat osteoporosis in high-risk patients, causes these side effects in more than 10% of users: leg cramps, dizziness, nausea, joint aches, and pain at the injection site.[1][2]
Serious Side Effects and Warnings
Rare but severe risks include orthostatic hypotension (low blood pressure when standing), increased blood calcium (hypercalcemia), kidney stones, and potential bone cancer (osteosarcoma) based on animal studies—human risk is unclear but leads to a black box warning limiting use to 2 years lifetime.[1][3] Allergic reactions like rash or swelling occur infrequently.
Side Effects by Frequency
- Very common (>10%): Dizziness, leg cramps, nausea, leg pain, injection site reactions.[2]
- Common (1-10%): Fatigue, headache, vomiting, muscle cramps, depression, insomnia, vertigo, arthralgia, pain in limbs.[2]
- Uncommon (0.1-1%): Hypercalcemia, urolithiasis, sciatica, neck pain.[2]
Who Experiences Side Effects Most?
Postmenopausal women report higher rates of nausea and dizziness; men see more leg cramps. Older patients (>65) have elevated dizziness risk due to orthostatic effects.[1][3]
How Long Do Side Effects Last?
Most like nausea or cramps resolve within days to weeks; injection pain fades in hours. Persistent symptoms warrant doctor contact.[3]
Managing Side Effects
Inject slowly to reduce pain; rise slowly from sitting to avoid dizziness. Stay hydrated for calcium balance. Report hypercalcemia signs (thirst, frequent urination) immediately.[1]
Forteo vs. Other Osteoporosis Drugs
Unlike bisphosphonates (e.g., Fosamax), Forteo builds bone rather than slows loss but carries cancer warning absent in those. Prolia users report more jaw issues; Forteo has unique hypercalcemia risk.[2]
[1]: FDA Forteo Label
[2]: Drugs.com Forteo Side Effects
[3]: Mayo Clinic Forteo