Drugs for Hypothalamic and Pituitary Disorders Flashcards
what are the clinical indications of somatotropin? (2)
recombinant human growth hormone, SC administered 6-7x/ week
- GH deficiency
- pediatric patients with short stature caused by factors other than GH deficiency (Prader-Willi, Turner, Noonan Syndromes, Idiopathic Short Stature)
what toxicities are associated with somatotropin in children and adults, respectively?
recombinant human growth hormone, SC administered 6-7x/ week
children - adverse effects rare, include intracranial pressure, scoliosis, edema, hyperglycemia (induced insulin resistance)
adults - peripheral edema, myalgias, arthralgia of hands/wrists, carpal tunnel
what is the clinical indication of mecasermin?
recombinant form of human IGF-1 approved for severe IGF-1 deficiency (not responsive to exogenous growth hormone)
adverse effect - hypoglycemia (related to activation of insulin receptors), requires consumption of carbohydrates with drug
octreotide vs pegvisomant
octreotide (also lanreotide): somatostatin agonist (GH antagonist)
pegvisomant: growth hormone receptor antagonist
used to treat smaller GH-secreting adenomas (larger adenomas treated with surgery/ radiation)
what toxicities are associated with octreotide?
long-acting somatostatin agonist —> reduces growth hormone production, SC injections every 8 hours
adverse effects: GI disturbance, gallstones, sinus bradycardia, conduction disturbances
what toxicities are associated with pegvisomant?
competitive growth hormone receptor antagonist, used to treat acromegaly, SC administration daily
adverse effects - flu symptoms, nausea, diarrhea, altered liver function tests (LFTs), contraindicated in patients with liver disease
what is the clinical indication of cabergoline and bromocriptine?
dopamine (DA) agonists, standard pharmacological treatment for hyperprolactinemia
what is considered complete vs partial success of cabergoline in women with anovulation?
dopamine agonist, used to treat hyperprolactinemia
complete success = pregnancy or 2 consecutive menses with evidence of ovulation
partial success = 2 menstrual cycles without evidence of ovulation or 1 ovulatory cycle
what toxicities are associated with cabergoline or bromocriptine?
dopamine agonists, used to treat hyperprolactinemia
adverse effects (most common reasons for therapy discontinuation) - nausea, headache, orthostatic hypotension, fatigue, delusions/hallucinations, contraindicated in patients with valvular heart disease
what are the clinical indications of Pitocin?
synthetic oxytocin, used to induce labor for conditions requiring early vaginal delivery
ex - uncontrolled maternal diabetes, worsening preeclampsia, intrauterine infection
also used for controlling uterine hemorrhage due to uterine atony (failure to contract) in immediate postpartum period
what toxicities are associated with synthetic oxytocin (Pitocin)?
serious toxicity is rare when used judiciously
toxicity due to excessive stimulation of uterine contractions (—> fetal distress, uterine rupture) or inadvertent activation of ADH (—> fluid retention, hyponatremia, seizures)
therefore, contraindicated in fetal distress, abnormal fetal presentation, or predispositions for uterine rupture
what is the effect of ADH (vasopressin) binding V1 vs V2 receptors?
V1 —> vasoconstriction (vasopressor action)
V2 —> renal fluid reabsorption (antidiuretic action)
does desmopressin act preferentially on V1 or V2 receptors?
long-acting ADH analog, preferentially binds V2
V1 —> vasoconstriction
V2 —> renal fluid reabsorption
used to treat central diabetes insipidus
what is the clinical indication of tolvaptan and conivaptan?
“-vaptans” = ADH receptor antagonists
preferentially bind V2 receptors (mediates antidiuretic actions), used to treat SIADH —> promote excretion of free water
note tolvaptan has risk of hepatotoxicity, limited to 30 day use
