If the BMD is worsening (outside the margin of the least significant change), this should prompt a reevaluation of teriparatide/abaloparatide therapy.

Common causes to consider:

• Medication nonadherence – teriparatide/abaloparatide requires daily subcutaneous injections
• There is an unaddressed/unrecognized/untreated secondary cause of osteoporosis.
  • Obtain labs: CBC, CMP, alkaline phosphatase, Phosphorus, magnesium, Parathyroid hormone, Thyroid function test,  25-hydroxy vitamin D, 24-hour urine calcium and creatinine (off calcium supplements, diuretics), +/- testosterone
  • Perform a medication review and address culprit medications if possible
• Consider evaluating for secondary causes of osteoporosis as guided by labs, history and physical exam:
  • For example, anemia and hyperproteinemia suggests multiple myeloma
  • a low vitamin D may suggest a malabsorption state caused by celiac disease
  • Consider additional evaluation

Consider alternative anabolic antiresorptive:

• The patient may have a poor response to teriparatide or abaloparatide therapy and needs a stronger agent
• Consider Romosozumab, although there is sparse data transitioning from a PTH analog.

Endocrinology consultation is needed for further guidance or if diagnostic uncertainty