Hypothalamus & Pituitary Drugs Flashcards
Somatotropin
- Recombinant Human GH (rhGH)
- SubQ, 6-7 x/week
- Alllows children to reach normal height, reverses some GH deficiency feat. in adults and can also use for other peds. conditions w/ short stature i.e. Prader willi, turner
Tox in Children: - very well tolerated - Pseudotumor cerebri, scoliosis progression, edema, hyperglycemia (rare adverse events)
Tox in Adults:- more adv. events common - Peripheral edema
- myalgias & arthralgias (esp. hands and wrist), carpal tunnel
- Very common but stop with lowering the dose
Mecasermin
- Recominant human IGF-1 (rhIGF-1)
- Tx for severe IGF-1 deficiency causing grown failure
- SubQ, 2x daily
Adverse Effects: Hypoglycemia- rhIGF-1 potentiates insulin action by activating the insulin rec. - Eat carbs 20 min before taking
Octreotide & Lanreotide
- Somatostatin analogs, decrease GH production
Octreotide: most widely used, SubQ every 8 hrs., decreases acromegaly sx - Lanreotide is comparable in normalizing GH and IGF-1 levels
Adverse Effects: - N/V, cramps - Gallstones
- Sinus bradycardia & conduction disturbances
Pegvisomant
- Competitive GH receptor antagonist
- Pegylated GH mutant that targets the GH rec. w/out causing signal transduction
- SubQ admin for 12+ weeks normalizes IGF-1 levels in acromegaly pt.
- well tolerated
Urofollitropin
Purified FSH prep from urine of post-menopausal women
Follitropin alpha & beta
Recombinant FSA
- shorter T1/2 than urofollitropin, more expensive
Lutropin-alpha
- Recombinant LH
- only approved in combo w/ Follitropin- alpha for stimulation of follicular development in infertile women w/ profound LH deficiency
HCG
2 Forms:
- Extracted and purified HCG from human urine
Choriogonadotropin-alpha: Recombinant HCG with more consistent bioactivity than urine purified form
Gonadotropis & HCG: Clinical uses and Toxicities
Clinical uses:
- Gonadotropins stimulate spermatogenesis and ovulation
- Controlled ovarian Stimulation in IVF
- Generally reserved for women who fail to ovulate w/ othr less complicated/less expensive mech
Toxicities/Complications:
- Multiple pregnancies (15-20%)
- Ovarian Hyperstimulation Syndrome (OHSS)- ovarian enlargement, hydrothorax, hypoventilation, can result in shock
Goserelin, Histrelin, Leuprolide, Nafarelin, Triptorelin
Relins
- Synth. GnRH agonists, suppress pulsatile GnRH release therefore suppressing FSH and LH secretion
Endometriosis: continuous tx w/ Leurpolide, Goserelin or nafarelin
Uterine Fibroids: Leurpolide, Goserelin or Nafarelin - 3-6 mo. tx shrinks fibroids + Fe for anemia
Prostate Cancer: Combo of continuous GnRH agonist + androgen receptor antagonist lowers serum testosterone - Leurpolide, goserelin, Histrelin and triptorelin approved
- Fluamide & Bicalutamide (anti-androgens)
Central Precocious Puberty: GnRH dependent CPP - Leurpolide- IM depot 1x/month
- Histrelin- implant 1x/year
- Tx continuously to age 11 in girls and age 12 in boys
Gairelix, Cetrorelix & Degarelix (Relixs)
- Synthetic GnRH receptor antagonists
- Inhibit LH/FSH secretion in a dose-dependent and more complete manner than GnRH agonists
Ganirelix &Cetrorelix: use in controlled ovarian hyperstimulation to lower risk of OHS vs. GnRH agonists
Degarelix: tx of advanced stage prostate cancer, causes sx of androgen deprivation i.e. hot flashes and edema
GnRH Agonist Toxicities (Relins)
Toxicities: Women
- Menopause sx- hot flashes, sweats, headache, depression, decreased libido, generalized pain, vag. dryness, breast atrophy
- Ovarian cysts may develop w/in first 2 mo. of treatment and generally resolve in 6 weeks- if not discontinue
- Decreased pone density & osteoporosis w/ prolonged use (monitor bone density)
Toxicities; Men
- Hot flashes, edema, decreased libido
- Decreased bone density, weakness
Bromocriptine & Cabergoline
- DA agonists; Ergot derivatives w/ high affinity for D2 rec.
- Standard tx for hyperprolactinemia
- Shrink PRL secreting tumors and lower circulating PRL levels to restore ovulation
- Complete success: pregnancy of 2 consecutive menses w/ ovulation
- Partial success: 2 menstrual cycles w/out ovulation or 1 ovulatory cycle
Toxicities: - Nausea, headache, orthostatic hypotension & fatigue
- Less nausea w/ cabergoline vs. bromocriptine
- Cabergoline- cardiac valvulopathy, contraindicated in pt. w/ pre-existing valvular disease
- Psych manifestations even at low doses- can take months to resolve
- Bromocriptine is drug of choice if pt. wants to get pregnant; Cabergoline is better tolerated
Pitocin
- Synthetic Oxytocin– increases frequency and force of uterine contractions
- Labor induction and control of postpartum hemorrhage due to uterine atony
Toxicities: - Excessive stimulation of uterine contractions before delivery – fetal distress, placental abruption, uterine rupture
- ADH rec. activation- excess fluid retention and water intox leading to hyponatremia, HF and seizures
Contraindications: - Fetal distress, abnormal fetal presentation, cephalopelvic disproportion, other predispositions for uterine rupture
Dutasteride & Finasteride
- 5-alpha- reductase inhibitors
- BPH tx- decrease prostate size and lower PSA levels
- May cause false neg. in PSA screening if cancer is present
