Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
Canada only Side effects:
italics
= common;
bold
= life-threatening
Nurse Alert
(lye-oh-thye′roe-neen)
Cytomel, Triostat
Func. class.:
Thyroid hormone
Chem. class.:
Synthetic T
3
Do not confuse:
Cytomel
/Cytotec
Increases metabolic rates, cardiac output, O
2
consumption, body temp, blood volume, growth, development at cellular level; exact mechanism unknown
Hypothyroidism, myxedema coma, thyroid hormone replacement, congenital hypothyroidism, nontoxic goiter, T
3
suppression test
Adrenal insufficiency, MI, thyrotoxicosis, untreated hypertension
Black Box Warning:
Obesity treatment
Precautions:
Pregnancy (A), breastfeeding, geriatric patients, angina pectoris, hypertension, ischemia, cardiac disease, diabetes
• Adult:
PO
25 mcg/day, increase by 12.5-25 mcg q1-2wk until desired response, maintenance dose 25-75 mcg/day, max 100 mcg/day
• Geriatric:
PO
5 mcg/day, increase by 5 mcg/day q1-2wk, maintenance 25-75 mcg/day
• Child >3 yr:
PO
50-100 mcg/day
• Child <3 yr:
PO
5 mcg/day, increase by 5 mcg q3-4days titrated to response, infant maintenance 20 mcg/day; 1-3 yr 50 mcg/day
• Adult:
PO
25-50 mcg then may increase by 5-10 mcg q1-2wk; maintenance dose 50-100 mcg/day
• Adult:
IV
25-50 mcg initially, 5 mcg in geriatric patients, 10-20 mcg with cardiac disease; give doses q4-12hr
• Adult:
PO
5 mcg/day, increase by 12.5-25 mcg q1-2wk; maintenance dose 75 mcg/day
• Adult:
PO
75-100 mcg/day × 1 wk; radioactive
131
I given before and after 1-wk dose
Available forms:
Tabs 5, 25, 50 mcg; inj 10 mcg/ml
•
In
AM
if possible as a single dose to decrease sleeplessness
•
At same time each day to maintain product level
•
Only for hormone imbalances; do not use for obesity, male infertility, menstrual conditions, lethargy
•
Lowest dose that relieves symptoms
•
Liothyronine after discontinuing other thyroid preparations
•
Do not give with calcium, iron, aluminum, magnesium, soy products
CNS:
Insomnia, tremors
, headache,
thyroid storm
CV:
Tachycardia, palpitations, angina, dysrhythmias
, hypertension,
cardiac arrest
GI:
Nausea, diarrhea, increased or decreased appetite, cramps
MISC:
Menstrual irregularities, weight loss, sweating, heat intolerance, fever, alopecia
PO/IV:
Peak 2-3 days, duration 72 hr, half-life 2.5 days
Increase:
effects of—anticoagulants, sympathomimetics, tricyclics, amphetamines, decongestants, vasopressors
Decrease:
absorption of liothyronine—cholestyramine; colestipol; calcium, iron, aluminum, magnesium products
Decrease:
effects of liothyronine—estrogens
Decrease:
thyroid hormone effect—soy
Increase:
CPK, LDH, AST, PBI, blood glucose
Decrease:
thyroid function tests
•
B/P, pulse periodically during treatment
•
Weight daily in same clothing, using same scale, at same time of day
•
Height, growth rate of child
•
T
3
, T
4
, which are decreased; radioimmunoassay of TSH, which is increased; radio uptake, which is increased if patient receiving too low a dose of medication
•
Patient may require decreased anticoagulant; check for bleeding, bruising
•
Increased nervousness, excitability, irritability, which may indicate too high a dose of medication, usually after 1-3 wk of treatment
•
Cardiac status: angina, palpitation, chest pain, change in VS
•
Removal of medication 4 wk before RAIU test
•
Therapeutic response: absence of depression; increased weight loss, diuresis, pulse, appetite; absence of constipation, peripheral edema, cold intolerance; pale, cool, dry skin; brittle nails; alopecia, coarse hair; menorrhagia; night blindness; paresthesia; syncope, stupor, coma
•
That hair loss will occur in child but is temporary
•
To report excitability, irritability, anxiety, which indicate overdose
•
Not to switch brands unless approved by prescriber
•
That hypothyroid child will show almost immediate behavior/personality change
•
That product is not to be taken to reduce weight
•
To avoid OTC preparations with iodine; to read labels; not to take with calcium, iron, aluminum, magnesium products
•
To avoid iodine-rich food, iodized salt, soybeans, tofu, turnips, high iodine seafood, some bread
•
That product controls symptoms but does not cure; that treatment is lifelong
Canada only Side effects:
italics
= common;
bold
= life-threatening
Nurse Alert
(lye′oh-trix)
Thyrolar, T
3
/T
4
Func. class.:
Thyroid hormone
Chem. class.:
Levothyroxine/liothyronine (synthetic T
4
, T
3
)
Do not confuse:
Thyrolar
/Thyrar
Increases metabolic rates, cardiac output, O
2
consumption, body temp, blood volume, growth, development at cellular level; exact mechanism unknown
Hypothyroidism, thyroid hormone replacement
Adrenal insufficiency, MI, thyrotoxicosis
Black Box Warning:
Obesity treatment
Precautions:
Pregnancy (A), breastfeeding, geriatric patients, angina pectoris, hypertension, ischemia, cardiac disease, diabetes
• Adult:
PO
single dose of Thyrolar, 1/4 or 1/2 of adult dose, adjust as needed at 2-wk intervals
• Geriatric:
PO
1/4 tab initially, adjust q6-8wk
Available forms:
Tabs: Levothyroxine 12.5 mcg/liothyronine 3.1 mcg; levothyroxine 25 mcg/liothyronine 6.25 mcg (Thyrolar-1/2); levothyroxine 50 mcg/liothyronine 12.5 mcg (Thyrolar-1); levothyroxine 100 mcg/liothyronine 25 mcg (Thyrolar-2); levothyroxine 150 mcg/liothyronine 37.5 mcg (Thyrolar-3)
•
Separate products containing calcium, iron by ≥4 hr
•
In
AM
if possible as a single dose to decrease sleeplessness
•
At same time each day to maintain product level
•
Only for hormone imbalances; do not use for obesity, male infertility, menstrual conditions, lethargy
•
Lowest dose that relieves symptoms
CNS:
Insomnia, tremors
, headache,
thyroid storm,
nervousness
CV:
Tachycardia, palpitations, angina, dysrhythmias
, hypertension,
cardiac arrest
GI:
Nausea, vomiting, diarrhea, increased or decreased appetite, cramps
MISC:
Menstrual irregularities, weight loss, sweating, heat intolerance, fever
PO (T
4
):
Onset unknown, peak 1-3 wk, duration 1-3 wk, terminal half-life 6-7 days
PO (T
3
):
Onset unknown, peak 24-72 hr, duration 72 hr, terminal half-life 1-2 days
Increase:
effects of amphetamines, decongestants, vasopressors, anticoagulants, sympathomimetics, tricyclics, catecholamines
Decrease:
absorption of liotrix—cholestyramine, colestipol
Decrease:
effects of liotrix—estrogens, phenytoin, carBAMazepine, rifampin
Decrease:
thyroid hormone effect—soy
Increase:
CPK, LDH, AST, PBI, blood glucose
Decrease:
thyroid function tests
•
B/P, pulse periodically during treatment
•
Weight daily in same clothing, using same scale, at same time of day
•
Height, growth rate of child
•
T
3
, T
4
, FTIs, which are decreased; radioimmunoassay of TSH, which is increased; radio uptake, which is increased if patient is receiving too low a dose of medication
•
May require decreased anticoagulant; check for bleeding, bruising
•
Increased nervousness, excitability, irritability, which may indicate too high a dose of medication, usually after 1-3 wk of treatment
•
Cardiac status: angina, palpitation, chest pain, change in VS
•
Withdrawal of medication 4 wk before RAIU test
•
Storage in airtight, light-resistant container
•
Therapeutic response: absence of depression; increased weight loss, diuresis, pulse, appetite; absence of constipation, peripheral edema, cold intolerance; pale, cool, dry skin; brittle nails; coarse hair; menorrhagia; night blindness; paresthesias; syncope, stupor, coma; rosy cheeks
•
That hair loss will occur in child, is temporary
•
To report excitability, irritability, chest pain, increased pulse rate, palpitations, excessive sweating, heat intolerance, nervousness, anxiety, which indicate overdose
•
Not to switch brands unless approved by prescriber
•
That hypothyroid child will show almost immediate behavior/personality change
•
That product is not to be taken to reduce weight
•
To avoid OTC preparations with iodine; read labels; separate products containing calcium, iron by ≥4 hr
•
To avoid iodine food, iodized salt, soybeans, tofu, turnips, high iodine seafood, some bread
•
That product does not cure but controls symptoms; treatment is lifelong