Thyroid Deck 2 Flashcards
Methimazole 10 to 50
10-50 times more active than propylthiouracil
Methimazole completely
Completely absorbed, but at variable rate
Methimazole slower
Slower excretion: 60-75% in urine in 48h
Methimazole half life
Half-life 6 hours
Methimazole onset of effects
Onset of effects in 1 week, peak 4-10 weeks
Methimazole crosses
Crosses placental barrier, caution in pregnancy
Methimazole is not
protein-bound
Propylthiouracil (PTU) rapidily
Rapidly absorbed, reaches peak after 1 hour
Propylthiouracil (PTU) incomplete
Incomplete absorption
Propylthiouracil (PTU) eliminated
Eliminated by kidney within 24 hours
Propylthiouracil (PTU) onset
Onset of effects in 10-21d, peak in 6-10 weeks
Propylthiouracil (PTU) crosses
Crosses placental barrier, but more highly protein-bound so crosses
less readily
Propylthiouracil (PTU) not secreted
Not secreted in breast milk in sufficient quantities to preclude breast
feeding
Adverse Effects of Thiourelynes or Thioamides
- Maculopapular pruritic rash
- Alopecia
- Drowsiness, headaches
- Fever, arthralgias
- Nausea and vomiting
- Nasal stuffiness
- Transient leukopenia
- Agranulocytosis (infrequent, but potentially fatal)
- Renal/hepatic failure
Monitoring Thiourelynes or Thioamides
• Thyroid studies, complete blood count (CBC), liver/renal
panels before starting drug
• Recheck in 1 to 2 months after starting drug.
Interactions Thiourelynes or Thioamides
• Don’t use with decongestants; vasopressor action not
well tolerated
• Lithium
• Warfarin
• Antidiarrheals: Kaolin action interferes with absorption
Corticosteroids two types
Glucocorticoids and Mineralcorticoid
Glucocorticoids role in
Adrenal cortex origin
Glucocorticoids originate in
Adrenal cortex origin
Glucocorticoids structure
Steroidal structure
Glucocorticoids part of the body
Part of body’s FB loop to reduce inflammation • Anti-inflammatory • Immunosuppressive • Antiproliferative
Glucocorticoids unique
receptors different from sex
steroids and mineralcorticoids
Mineralcorticoid class of
Class of steroid hormones that cause
Na and H20 retention
Mineralcorticoid primary example
Aldosterone comes from adrenal
cortex
• Essential to maintenance of
adequate fluid volume (CO/BP)
Long acting glucocorticoid
Dexamethasone
Glucocorticoid use in allergy and pulmonary
Asthma, allergic rhinitis, uricaria,anaphylaxis, food/drug
allergy
Glucocorticoid use in skin
Acute severe dermatitis
Glucocorticoid use in endocrinology
Adrenal disorders
Glucocorticoid use in GI
IBD: Crohn’s Disease; ulcerative colitis
Glucocorticoid use in hematology
Leukemia, lymphoma
Glucocorticoid use in ophthalmology
Uveitis
Glucocorticoid use in rheumatology
RA, SLE, vasculitis
Glucocorticoid other use
MS, organ transplant, nephrotic syndrome, cerebral
edema
crushing’s syndrome S/S
C – Cataracts U – Ulcers S – Striae, Skin thinning H – Hypertension, Hirsutism I – Immunosuppression, Infections N – Necrosis of femoral heads G – Glucose elevation O – Osteoporosis, Obesity I – Impaired wound healing D – Depression/mood changes
Addison’s disease is an
Impaired adrenocortical hormone synthesis
• Primary: adrenal steroidogenesis impairment
• Secondary: pituitary adrenocorticotropic hormone deficit
• Tertiary: hypothalamic corticotropin-releasing hormone deficit
Symptoms of Addisons Disease
Low BP, HypoNa, HyperK+, Hypoglycemia, fatigue, anorexia, weight loss, hyperpigmentation
Initial testing for adisons diseas
AM cortisol, Low DHEA-S for age and sex, ACTH test, BUN, CBC, Electrolytes plasma aldosterone
(renin)
Treatment for Addisons disease
Treatment –Glucocorticoid replacement; Individualize!
• Challenges
• Inability to replicate circadian cortisol rhythm
• Uncertainties in dose adjustment and treatment monitoring
• Side effects of inadequate replacement; reduced QOL
Tapering Corticosteroids there is no
standard taper
Tapering Corticosteroids required if
Required if more than 2 weeks continuous
glucocorticosteroids
Tapering Corticosteroids longer taper for
Longer taper for higher doses and longer-acting systemic
glucocorticoids
• Weeks to months to allow recovery of H-P-A axis
