Term
initiating insulin therapy in adults w/ DM type 1: dose |
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Definition
- usually 0.6 units/kg
- other recommendation: 0.5-1.0 units/kg
- both basal (long or intermediate acting, usually compromising 40-60% of the total daily dose) and rapid or short acting around meals are recommended
- basal insulin provides coverage for 24hrs & covers periods btwn meals & at nights; also inhibits hepatic gluconeogenesis during fasting periods
- insulin glargine provides 24hr peakless coverage that aids in reducing possible hypoglycemia
- ultra-rapid or regular insulin provides improved postprandial coverage from CHO meals
- less nocturnal hypoglycemia from ultra-rapid preparations
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Term
initiating insulin therapy in adults w/ DM type 1: long-term insulin therapy: dose |
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Definition
0.6-0.8 units/kg/day pts w/ DM type 2 - if insulin needed, doses vary |
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Term
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Definition
after initial therapy is instituted this phase occurs & may last 12-18 months; insulin dosages may be reduced to 0.2-0.5 units/kg/day *important to tell pts about this phase to prevent false beliefs that the diabetes is partially cured |
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Term
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Definition
morning rebound hyperglycemia; occurs in response to nocturnal hypoglycemia w/ excessive insulin administration clues: erratic plasma glucose & urine ketone values; symptoms of nocturnal hypoglycemia (night sweats, nightmares, low serum glucose 2 to 3 am), weight gain in presence of heavy glycosuria |
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Term
| treatment for somogyi phenomenon |
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Definition
reduction in insulin dose 10-20% distiguish from down phenomenon which is early morning fasting hyperglycemia w/o nocturnal hypoglycemia; thought to be related to circadian/rhythm secretion of growth hormone and treated by evening or bedtime dose of insulin |
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Term
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Definition
- in the normal 120-day life splan of the RBCs, glucose molecules join Hgb, forming glycosylated hemoglobins (Hgb A1A, Hgb A1B, Hgb A1C - most common type)
- once a Hgb molecule is glycosylated, it remains that way
- build-up of glycosylated Hgb within the red cell reflects the average level of glucose to which the cell has been exposed during its life cycle
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Term
| adverse effects of glycosylated hemoglobin |
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Definition
- weight gain
- urticaria
- allergic rxns (may lead to anaphylaxis)
- lipohypertrophy: increased fat at injection site
- lipoatrophy: loss of fat at injection site
- hypoglycemia: tremors, sweating (diaphoresis), pallor, restlessness, hunger, HA, weakness, confusion, seizures
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Term
| contraindications of glycosylated hemoglobin |
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Definition
- hypersensitivity
- used w/ caution when food intake is reduced or exercise is increased b/c insulin may reduce glucose to lethal levels (can cause hypoglycemia)
- ETOH (only very sugary preparations), estrogens, glucocorticosteroids, nicotine, thiazide diuretics, thyroid preps: increased blood glucose levels
- BBs may mask s/s of hypoglycemia & further reduce glucose levels
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Term
| nursing considerations with glycosylated hemoglobin |
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Definition
- check blood glucose levels at the time of the insulin's peak action to monitor for hypoglycemia
- monitor pt's BP, I/O, blood glucose level, and ketones every hour when administering IV insulin as a tx for DKA (always for type 1)
- insulin doses must be adjusted during times of stress, infection, or pregnancy
- insulin must be injected SC (only regular can be IV) at 90 degree angle to prevent local reactions
- do not shake vials; roll in palm of hand
- discard if vials have clumping, discoloration, solid deposits, or granular appearance
- do not mix glargine w/ any other insulin (will become regular)
- blurred vision may occur but will subside in 6-8wks
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Term
oral hypoglycemics (for type 2) insulin-secretagogues: long acting sulfonylureas |
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Definition
- 1st generation: currently not used, may drug interactions & side effects
- 2nd generation: glipizide (Glucotrol)
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Term
| pharacodynamics for insulin secretagogues (sulfonylureas) |
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Definition
- bind to potassium channels on the B cells of the pancreas, stimulating the pancreas to release insulin
- incrase the sensitivity of the peripheral insulin receptors, which increases insulin binding in the peripheral tissues
- decrease hepatic glucose production (b/c stim insulin secretion so neg. feedback loop initiated)
- pt must have functional pancreatic B cells that are able to produce insulin for sulfonylureas to work
- equally efficacious as a group
- can degrease FPG by 60-70 mg/dL & HBA1C by 1.5-2% points
- netural effect on lipids
- usually well tolerated : hypoglycemia most common side effect, also associated w/ some weight gain (7-10lbs)
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Term
| pharmacodynamics of sufonylureas |
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Definition
- well absorbed after PO admin: should be administered 30 min before meals
- all can be taken w/ food
- metabolized by the liver & excreted in urine
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Term
| adverse effects of sulfonylureas |
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Definition
- weight gain
- GI (nausea, emesis, anorexia, epigastric discomfort, heartburn)
- hypoglycemia (so if not eating, do not take it)
- photosensitivity (b/c sulfa drug)
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Term
| contraindications of sulfonylureas |
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Definition
- hypersensitivity
- severe hepatic & renal impairment (measured by increased creatine in circ due to decreased excretion in urine)
- DM type 1
- complications of DM type 2 (severe infections, major surgery, trauma, coma)
- not intended to use during pregnancy, lactation, or by children
- interact w/ drugs that potentiate the effects of sulfonylureas and probenecid & ETOH
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Term
| nursing considerations with sulfonylureas |
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Definition
- instruct pt of the exact times at which the oral antidiabetic should be taken for maximal effectiveness; if a dose is missed, should be takn as soon as remembered but should never be doubled
- instruct pt to wear sunscreen
- 2nd generation sulfonylureas are more potent, produce fewer adverse rxns, and have longer duration times than do 1st generation
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Term
oral hypoglycemics insulin secretagogues - short acting: meglitinides |
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Definition
d-phenylalanine derivative - nateglinide (Starlix) - short-acting glucose-lowering drugs
- stimulate endogenous insulin release to reduce postprandial (after meal) glucose level
- stimulate the B cells of the pancreas to release insulin on demand, thus functioning B cells must exist for this action to occur
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Term
| pharmacokinetics of meglitinides |
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Definition
- have short 1/2 life (1hr) & a short duration of action leading to rapid apperance in the early postprandial state
- metabolized in the liver; do not cause hepatocellular dysfunction; can be used w/ renal impairment
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Term
| pharmacotherapeutics of meglitinides |
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Definition
- FDA approved as monotherapy or in combo w/ metformin
- expensive
- given preprandially; if meal is skipped, the dose should be omitted
- Starlix: recommended dose of 120 mg before each meal
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Term
| adverse effects of meglitinides |
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Definition
- side effects weight gain, hypoglycemia & GI discomfort
- no noted drug interactions
- instruct pt to take within 30 min before meals; when the pt skips a meal, a dose that is scheduled before the meal should also be skipped to decrease risk of hypoglycemia
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Term
insulin secretagogues - short acting biguanides |
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Definition
metformin (Glucophage) - acts by decreasing hepatic gluconeogensis & to a lesser extent by enhancing peripheral glucose uptake (primarily muscles)
- well absorbed orally
- not bound to serum proteins & not metabolized
- excretion v ia urine
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Term
| pharmacotherapeutics of biguanides |
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Definition
- at present, first line agent in DM type 2 therapy, especialy in obese pts & in pts w/ dyslipidemia
- can decrease FPG by 60-70 mg/dL & HbA1C by 1.5-2 & when in combo w/ sulfonylureas have additive effect & further reduction of HgA1C by 1.5-2%
- additional benefits: causes weight loss; decreases tirglycerides & LDL levels by 10-15% and slight increase in HDL level; less liely to cause hypoglycemia; the only oral agent shown to reduce macrovascular complications
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Term
| adverse effects of biguanides |
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Definition
- most common GI problems: metallic taste in mouth, mild anorexia, nausea, abdominal discomfort & diarrhea; usually transient & reversible
- should be discontinued for 48hrs after any radiologic procedure involving IV admin. of iodinated contrast material; should be withheld in any pts undergoing major surgery
- rare problem: lactic acidosis
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Term
| contraindications of biguanides |
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Definition
- relative or absolute contraindications to metformin therapy:
- renal insufficiency (serum creatine > 1.5)
- concurrent liver disease or ETOH abuse
- CHF
- PMH of lactic acidosis
- severe infection w/ decrease tissue profusion
- hypoxic states
- serious acute illness
- hemodynamic instability
- age 80 yrs or more (b/c prone to lactic acidosis)
- drug interactions w/ ETOH b/c increase the risk of lactic acidosis
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Term
| nursing considerations with biguanides |
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Definition
- hold metformin for 48 hrs after diagnostic studies in which the pt is administered iodinated contrast dye to prevent lactic acidosis or renal failure from occuring
- admin metformin w/ meals to reduce GI side effects
- bitter metallic taste may occur but will subside as will other GI symptoms
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Term
insulin secretagogues - short acting thiazolidinediones (often called glitazones) |
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Definition
rosiglitazone (Avandia) pioglitazone (Actos) |
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Term
| pharmacodynamics of thiazolidinediones (glitazones) |
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Definition
- lower glucose levels by increasing insulin sensitivity - increasing glucose uptake in muscle & adipose tissue & lowering hepatic glucose production
- more powerful than metofrmin in increasing glucose uptake in muscles & adipose tissue but not as effective in lowering hepatic glucose production than metformin
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Term
| pharmacotherapeutics of glitazones |
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Definition
- indicated as monotherapy & in combo w/ metformin & sulfonylureas; monotherapy is less effective than either metformin or sulfonylureas (much more expensive too)
- lower FPG by 60-80 mg/dL & HbA1C by 1-1.6% when used w/ sulfonylureas, additional lowering of HbA1C up to 1-2%
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Term
| contraindications of glitazones |
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Definition
- may cause fluid rentention & weight gain; should not be used in serve CHF
- hypersensitivity
- heptic dysfunction
- may reduce the effectiveness of oral contraceptives
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Term
| adverse effects of glitazones |
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Definition
well tolerated back pain, diarrhea, fatigue fluid retention - peripheral edema (benign) dose related moderate weight gain |
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Term
| nursing considerations of glitazones |
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Definition
- may be administered w/o regard for meals
- avoid discontinuing meds w/o consultation
**pioglitazone has an excellent lipid profine so more beneficial of the two forms
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Term
alpha-glucosidase inhibitors |
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Definition
miglitol (Glyset) - very short acting, rarely used
- act by delaying digestion & absorption of CHO from the GI tract; inhibit alpha-glucosidase enzymes in the small intestine & alpha-amylase in the pancreas, decreasing the rate of CHO metabolism & lowering postprandial blood glucose by up to 50 mg/dL; used for this reason (act as resins & are released in stool)
- should only be taken when CHO is in the meal
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Term
| pharmacotherapeutics of alpha-glucosidase inhibitors |
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Definition
- in combo w/ sulfonylureas, metformin, or insulin
- adverse effects: diarrhea & flatulence in up to 30% of pts; low staring dose to decrease side effects; should be taken w/ first bite of meal
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Term
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Definition
- facilitates normal growth & maturation by maintaining the level of metabolism in the tissues that is optinal for their normal function
- composed of multiple follicles, each of which has a lumen filled w/ thyroglobulin (colloid), the storage form of the thyroid hormone. The follicles are surrounded by parafollicular cells that produce calcitonin
- thyroid hormone has important effects on virtually every tissue of the body; these effects result from the interaction of thyroid hormone w/ its receptor
- thyroid hormone takes its part in the regulation of metabolic rate, gasterintenstinal motility, cardiac contractility, HR, body temp, mood, body weight & skin texture
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Term
| hypothalamic-pituitary-thyroid axis |
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Definition
negative feedback loop - hypothalamus works w/ the pituitary gland to regulate the production of bioavailable thyroid hormone
- hypothalamus secretes thyrotropin-releasing hormone (TRH) into the pituitary portal system
- TRH stimulates the production of thyroid-simulating hormone (TSH) by the anterior pituitary gland
- TSH, which is produced in a pulsatile manner w/ 2-3 peaks/day, stimulates the production of thyroid hormones (thyroxine-T4 & triidothyronine-T3) by thyroid follicular cells located in the thyroid gland
- T3 is 10x more potent than T4; in fact, most of the systemic effects of the thyroid hormones are due to T3, b/c T4 is converted to T3 in the peripheral tissues, liver & kidney
- thyroid hormones are largely bound to thyroxine-binding globulin (TBG); 98% of T3 & 99.8% of T4 are bound to plasma proteins; only the free form has metabolic activity
- circulating levels of T4 & T3 provide neg. feedback for hypothalamic production of TRH & pituitary production of TSH; this system produces stable levels of T4 & T3 in healthy people
- measurement of the serum TSH level is the most important test in evaluation of the HPT axis
- b/c most thyroid disease result from the dysfunction of the thyroid gland rather than pituitary or hypothalamic disease, the TSH level is usually the first parameter to become abnormal during the development of thyroid disease
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Term
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Definition
- metabolic imbalance resulting from excessive thyroid hormone production
- grave's disease is the most common form (autoimmune hyperthyroidism)
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Term
| pathophysiology of hyperthyroidism |
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Definition
- autoimmune disorder; TSI - thyroid-stimulating immunoglobulin stimulates TSH receptors (pretends it's TSH)
- excessive secretion of thyroid hormoneleads to increased metabolic rate, excessive heat production & increased responsiveness to catecholamines; these actions lead to profound changes in many organ systems
- severe acute exacerbation (i.e. thyroid storm) may be life-threatening, emergent complication
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Term
| clinical manifestations of hyperthyroidism |
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Definition
- nervousness, irritability, hyperactivity, emotional lability, and decreased attention span
- weakness, easy fatigability & exercise intolerance
- heat intolerance
- weight change (loss or gain) & increased appetite
- insomnia & interrupted sleep
- frequent stools/diarrhea
- menstrual irregularities & decreased libido
- warm, sweaty, flushed skin w/ a velvety-smooth texture & spider telangiectasias
- tremor, hyperkinesia, and hyperreflexia
- exophthalmos (protruding eyeballs), retracted eyelids, and staring gaze
- hair loss
- goiter
- bruits over thyroid gland
- elevated systolic BP
- atrial fibrillation
**collectively, these symptoms are called thyrotoxicosis (not necessarily hyperthyroidism) |
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Term
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Definition
medical emergency (untreated hyperthyroidism) tx needs to be aggressive - hyperthermia
- hypertension
- delirium
- vomiting and abdominal pain
- tachydysrrhythmias
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Term
| treatment for hyperthyroidism |
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Definition
- antithyroid medications
- symptomatic tx: BBs reduce the tremulousness & tachycardia associated w/ hyperthyroidism
- antithyroid drugs
- radioactive iodine (IDEAL)
- surgery
- less frequently considered option due to potential complications (hyperparathyroidism & vocal cord paralysis)
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Term
antithyroid drugs thioamides |
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Definition
propylthiouracil (PTU) (Propacil) - drugs used for hyperthyroidism are designed to block or antagonize the effects of hormones secreted from thyroid gland
- prognancy category D; can cause neonatal hypothyroidism
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Term
| pharmacodynamics of thioamides |
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Definition
- block iodine's ability to combine w/ tyrosine, thereby preventing thyroid hormone synthesis (formation of T3 & T4)
- PTU also inhibits the conversion of T4 to T3
- have no effect on the thyroglobulin already stored in the gland; therefore observation of any clinical effects of these drugs may be delayed until thyroglobulin stores are depleted
- effects are slow in onset; these drugs are not effective in thyroid storm
- PTU lowers serum T3 faster than methimazole, more frequently used when more rapid improvement is needed
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Term
| pharmacotherapeutics of thioamides |
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Definition
- grave's disease
- thyrotoxicosis
- supression of thyroid hormon synthesis until radiation therapy destroys thyroid tissue
- suppression of thyroid hormone synth before thyroid surgery to reduce risk of thyroid crisis
- tx of thyroid crisis
- requires 1-2 wks before effects noticed (add BBs for symptomatic tx)
- may take around 12 mo of tx to achieve euthyroid (normal) status
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Term
| pharmacokinetics of thioamides |
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Definition
- good oral absorption: 80-90% is bioavailable
- PTU - short 1/2 life (1-2 hrs in serum), however drug persists in thyroid gland, allowing for TID dosing
- widely distributed but concentrated in the thyroid gland
- excretion through the kidney
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Term
| contraindications of thioamides |
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Definition
- hypersensitivity (PTU - sulfa drugs)
- caution in pregnancy - PTU is preferred over methimazole in pregnant women b/c its rapid action reduces transfer across placenta & b/c it doesn't cause aplasia cutis (lesion w/ no hair formation and skin changes) in fetus
- lactation - neonatal hypothyroidism
- bleeding disorders
- diabetes
- lithium therapy
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Term
| drug/food interactions with thioamides |
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Definition
- anticoagulants: action may be enhanced
- lithium: simultaneous use may potentiate hypothyroidism
- diuretics: increased K-losing effect
- antidiabetic agents: incrased requirements for insulin & oral hypoglycemics
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Term
| adverse effects of thioamides |
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Definition
- relatively rare
- most common: rash, edema, paresthesia, myalgia
- agranulocytosis (severe, acute neutropenia - decreased # of WBCs) (granulocytopenia) - won't be able to fight infections
- occurs in only 1/500; reversed by discontinuation of drug therapy; rare, but most important effect to watch for; more risk w/ PTU than w/ methimazole
- usually asyptomatic but may maifest as persistent (or severe) fever or chills, sore throat & throat infections, cough, or mouth sores
- risk much more increased after 40 yrs of are & is not dose-related
- hypothyroidism: excessive suppression
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Term
| nursing considerations with thioamides |
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Definition
- take PTU around the clock to ensure consistent levels (evey 8hrs instead of TID)
- know that the most serious adverse effect of antithyroid drugs is agranulocytosis (monitor CBC for leukopenia)
- supplemental MVI, Ca & vit D to rebuild the bone density
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Term
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Definition
not frequently used potassium iodide (SSKI) strong iodine solution (Lugol's solution) - giving iodides would seemto exacerbate s/s of hyperthyroidism
- giving iodides in large doses actually decreases release of thyroid hormone
- also, iodides decrease the vascularity & size of the thyroid gland
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Term
| pharmacotherapeutics of iodide products |
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Definition
- rarely used as a sole therapy
- most often used before surgery or in conjunction w/ a thioamide in thyrotoxic crisis (thyroid storm)
- stable iodine is also used after radioactive iodine therapy to control symptoms of hyperthyroidism while radiation takes effect
- not useful for long-term therapy b/c the thyroid ceases to respond to the drug after a few weeks
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Term
| contraindications of iodide products |
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Definition
- iodide hypersensitivity
- drug interactions:
- potassium supplements, K-sparing diuretics, ACE inhibitors: hyperkalemia
- lithium: increased hypothyroid action
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Term
| adverse effects of iodide products |
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Definition
- relatively minor
- sore mouth, throat
- brassy taste & burning in the mouth
- coryza (nasal discharge) & sneezing that stimulates a cold
- ulcerations of mucus membranes
- staining of the teeth (use straw)
- anapylactoid rxn (if allergy)
- hypothyroidism
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Term
| nursing considerations with iodide products |
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Definition
- dilute the drug in full glass of H20, fruit juice, or milk & admin after meals
- monitor weight, pulse, and thyroid status
- instruct pt to avoid aspirin & products containing iodine: iodized salt, shellfish & OTC cought medicine
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Term
| radioactive iodine: 131 I |
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Definition
- b/c the thyroid gland avidly takes up iodine, a dose of radioactive iodine can ablate thyroid tissue, which results in permanent reduction of thyroid activity
- destroys thyroid tissue, through induction of acute radiation thyroiditis & chronic gradual thyroid atrophy; acute radiation thyroiditis usually occurs 3-10 days after tx; chronic thyroid atrophy may take several years to appear
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Term
| pharmacotherapeutics of radioactive iodine |
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Definition
- most common form of tx for Grave's disease in US
- used in adults over 21 yrs old who have hyperthyroidism; increasingly recommended in kids
- single dose successfully treats hyperthyroidism in 95% of pts; in 5% of pts a 2nd dose is necessary to complete tx
- slow tx, effects may take 8-26 weeks to occur
- contraindicated in pregnancy/lactation - teratogenic
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Term
| adverse effects of radioactive iodine |
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Definition
- no evidence exists that 131 I increases the risk for developing cancer in the doses used to treat grave's
- transient worsening of symptoms before improvement
- high incidence of delayed hypothyroidism (10-20 yrs to develop)
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Term
| nursing considerations with radioactive iodine |
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Definition
- do not kiss, exchange saliva, or share food or eating utensils for 5 days after tx; dishes should be washed in a dishwasher
- avoid close contact w/ infants, young kids (under 8 yrs), and pregnant women for 5 days (you can be in the same room)
- if you have an infant, no breast feeding allowed
- flush toilet twice after urinating and wash hands
- if sore throat or neck paoin, take acetaminophen or aspirin (expected)
- if you note increased nervousness, tremulousness, or palitations, call physician
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Term
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Definition
- undersecretion of thyroid hormone from the thyroid gland
- 5-10/1000 in general population; over age 65 increases to 6-10% of women, and 2-3% of men; predominant age: over 40; predominant sex: female, 5-10:1
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Term
| pathophysiology of hypothyroidism |
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Definition
- primary hypothyroidism - most common form
- most liekly autoimmune disease; may occur as a sequel to Hashimoto's thyroiditis (chronic thyroiditis)
- post-therapeutic hypothyroidism - 2nd most common cause
- radioactive iodine; surgery or thyroidectomy; thioamide drugs
- transient hypothyroidism that is associated w/ acute or subacute thyroiditis (sometimes viral etiology)
- normal T4 and mildly increase TSH is found in subclinical hypothyroidism; tx controversial (if symptoms are significant and prolonged, therapy should be started)
- hypothyroidism can occur after hyperthyroidism in women following pregnancy (postpartum thyroiditis)
- painless subacute thyroiditis leading to transient hypothyroidism lasting ~3mo
- tx w/ replacement therapy may be nec.
- up to 30% pts develop permanent hypothyroidism
- less common causes include iodine ingestion, neck irritation, certain meds (lithium) & malfunctioning of the hypothalamic-pituitary axis
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Term
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Definition
| this is what we're trying to avoid; severe hypothyroidism; may lead to coma |
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Term
| clinical manifestations of hypothyroidism |
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Definition
- fatigue
- weight gain
- dry skin w/ cold intolerance
- yellow skin
- coarseness or loss of hair
- hoarseness
- goiter
- reflex delay
- ataxia
- constipation
- memory & mental retardation
- decreased conc
- depression
- irregular or heavy menses & infertility
- myalgias
- hyperlipidemia
- bradycardia & hypothermia
- myxedema fluid infiltration of tissues
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Term
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Definition
hypothyroidism in infants so, all are screened after 24 hrs of life; most important test |
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Term
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Definition
thyroid hormone replacement therapy all pregnancy cat. A |
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Term
thyroid replacement hormones desiccated thyroid - armour, etwon & others |
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Definition
- naturally occuring thyroid hormone from thyroid glands or pigs or beef
- contains both levothyroxine & liothyronine that possess all the actions of endogenous thyroid hormones
- absorption is erratic & often incomplete when administered PO
- average bioavailability 50-75%
- most expensive form of therapy
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Term
thyroid hormone replacement therapy levothyroxine (T4) - synthroid, levothroid & others |
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Definition
- synthetically prepared levo isomer of thyroxine (human)
- provides only T4 typically 80% of dose is deiodinated to T3
- advantages of these preps over desiccated tyroid include reliable potency &the absence of wide swings in serum T4 & T3 levels
- highly protein bound (>99%)
- half-life is 6-7 days in euthyroid pts & 9-10 d ays in hypothyroid pts
- early pts are very sensitive to T4, so start at lower doses
- takes up to 6-8 wks to reach steady state
- good for maintaining steady state
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Term
thyroid replacement hormones liothyronine (T3) - cytomel, triostat |
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Definition
- synthetic hormone
- 2-3x more potent than T4
- due to faster onset of action greater activity recommended for tx of myxedema coma
- biological half-life is 2.5 days - faster dosage adjustments (titration) may be beneficial in case of overdosing
- not protein bound - doses fully bioavailable
- cleared from the body faster than T4 & provides a reliable source for both T3 & T4 replacement
- stabilization of metabolism for the pt on T3 is more difficult
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Term
| general info about thyroid replacement hormones |
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Definition
- levothyroxine = drug of choice for thyroid hormone replacement & thyroid-stimulating hormone supression therapy
- someevidence suggests that some pts (especially those who still feel tired or depressed even w/ normal TSH & T4 levels) may feel better if they are given both levothyroxine (T4) & triiodothyronine (T3); the combo seems to improve mood, energy & mental alertness for some hypothyroid pts
- researchers suggest lowering the levothyroxine dose by 50 mcg & adding 10-12.5 mcg of triiodothyronine (Cytomel)
- too much T3 can cause palpitations & tremors
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Term
| route of administration & evaulation of thyroid replacement hormones |
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Definition
- PO admin - on empty stomach; best in AM
- clinical improvement evaluated
- serum TSH levels (decrease) evaluated
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Term
| adverse effects of thyroid replacement hormones |
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Definition
- in appropriate doses - very safe & well tolerated
- in doses too high - s/s of hyperthyroidism
- in doses too low - s/s of hypothyroidism
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Term
| precautions & drug interactions of thyroid replacement hormones |
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Definition
- elderly - need much lower doses to prevent excessive cardiac stimulation
- variability in bioavailability among brands
- drug interactions:
- Ca, aluminum-based antacids, iron preps & bile acid sequestrants interfere w/ levothyroxine absorption from the stomach; they must be spaced about 4 hrs apart
- antidiabetic drugs & digitalis: decreased effectiveness of these drugs
- aspirin, phenytoin: enhanced action of thyroid hormone
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Term
| nursing considerations with thyroid replacement hormones |
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Definition
- report weight gain of 2lbs/week or more
- take drugs at same time each day, preferably in AM before eating
- avoid foods that can inhibit thyroid secretion (strawberries, peaches, cabbage, spinach, kale, radishes, peas)
- do not take Ca, etc. w/ thyroid hormones
- dosage of insulin and oral antidiabetic drugs may need to be increased
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