TERIPARATIDE
Clinical safety rating: safe
Animal studies have demonstrated safety
Teriparatide is a recombinant fragment of human parathyroid hormone (PTH 1-34). It acts by stimulating osteoblast activity, increasing bone formation, and improving bone microarchitecture.
| Metabolism | Teriparatide is metabolized via non-specific proteolytic degradation in the liver and peripheral tissues. No specific cytochrome P450 enzymes are involved. |
| Excretion | Primarily hepatic metabolism via nonspecific proteolytic enzymes; no significant renal or biliary excretion; minimal unchanged drug in urine or feces. |
| Half-life | Terminal half-life approximately 1 hour following subcutaneous administration; clinical duration limited by rapid clearance, necessitating once-daily dosing. |
| Protein binding | Approximately 40-50% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Approximately 0.2-0.3 L/kg, indicating distribution largely confined to extracellular fluid and bone. |
| Bioavailability | Subcutaneous: approximately 95% bioavailability. |
| Onset of Action | Subcutaneous: Onset of serum calcium elevation within 2-4 hours; peak bone formation marker response occurs within 24 hours. |
| Duration of Action | Duration of pharmacological effect (elevated serum calcium) lasts approximately 4-6 hours; once-daily dosing maintains intermittent PTH exposure. |
20 mcg subcutaneously once daily.
| Dosage form | SOLUTION |
| Renal impairment | No dose adjustment required for mild to moderate renal impairment (CrCl >30 mL/min). Not recommended in severe renal impairment (CrCl ≤30 mL/min) due to lack of data. |
| Liver impairment | No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh class A or B). Not studied in severe hepatic impairment (Child-Pugh class C). |
| Pediatric use | Not approved for use in pediatric patients; safety and efficacy not established. |
| Geriatric use | No dose adjustment required; clinical studies included patients >65 years with no significant differences in efficacy or safety. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
No significant drug interactions Can cause orthostatic hypotension and increased risk of osteosarcoma.
| Breastfeeding | No human data; teriparatide likely excreted in milk in low amounts. M/P ratio unknown. Recommend caution or avoid breastfeeding. |
| Teratogenic Risk | Insufficient human data; animal studies show skeletal abnormalities at high doses. No known risk in first trimester; avoid in second and third trimesters due to potential fetal skeletal effects. |
| Fetal Monitoring |
■ FDA Black Box Warning
Increased risk of osteosarcoma in animal studies. Avoid use in patients with Paget's disease of bone, unexplained elevations of alkaline phosphatase, open epiphyses, prior radiation therapy involving the skeleton, or bone metastases.
| Common Effects | Dizziness |
| Serious Effects |
["Paget's disease of bone","Unexplained elevations of alkaline phosphatase","Open epiphyses (pediatric patients)","Prior radiation therapy involving the skeleton","Bone metastases or history of skeletal malignancies","Metabolic bone diseases other than osteoporosis","Pregnancy and lactation","Hypersensitivity to teriparatide or any component"]
| Precautions | ["Risk of osteosarcoma (see black box warning)","Orthostatic hypotension may occur, especially with initial doses","Hypercalcemia may occur; monitor serum calcium","Use with caution in patients with active urolithiasis","May increase serum uric acid"] |
Loading safety data…
| Monitor serum calcium and phosphate levels in mother; consider fetal ultrasound for skeletal development if exposed in second/third trimester. |
| Fertility Effects | No adverse effects on fertility observed in animal studies; limited human data. |