Treatment of hypopituitarism in patients receiving antiepileptic drugs

Hormonal Replacement in Hypopituitarism in Adults: An Endocrine Society Clinical Practice Guideline

“…Some AEDs enhance hepatic CYP450 isoenzyme activity (e.g., phenytoin, carbamazepine, oxcarbazepine, and topiramade), accelerating the hepatic metabolism of hormonal preparations and decreasing serum concentrations of relevant hormones (268). Effects depend on the type of GC.…”

“…Dexamethasone is metabolized primarily by hepatic CYP3A4 (269), and patients may need to increase dexamethasone doses (268). AEDs only modestly decrease the concentrations of prednisone and prednisolone (270).…”

“…Other AEDs increase SHBG, leading to the reduced bioavailability of E2 and T (268), which may compromise the efficacy of hormonal treatment. Combined estrogen and progesterone may decrease lamotrigine levels (276), and endogenous and exogenous sex steroids may affect seizure activity and epilepsy in women (277).…”

The effects of antiepileptic inducers in neuropsychopharmacology, a neglected issue. Part I: A summary of the current state for clinicians

“…The inductive effects are also observed when sexual hormones are administered for treating hypopituitarism. 113 The effect of potent inducers on endogenous female and male sexual hormones appears more limited, although in rare cases they can be associated with diminished potency in men and menstrual disorders in women. 114 Vitamin D, as with sexual hormones, is a derivative compound of cholesterol; potent inducers definitively interfere with its metabolism, which is mediated by CYPs, resulting in the potential for osteoporosis.…”

“…Occasionally, oxcarbazepine has also been associated with hypothyroidism. 113,117 In the author's experience, thyroid abnormalities are more likely when the endogenous feedback is impaired and frequent when thyroid medication is administered exogenously and the body cannot compensate for the mild thyroid dysfunction caused by AEDs.…”