Mosby's 2014 Nursing Drug Reference (260 page)
Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
(meth-im′a-zole)
Tapazole
Func. class.:
Thyroid hormone antagonist (antithyroid)
Chem. class.:
Thioamide
Do not confuse:
methimazole
/metoprolol/minoxidil
Inhibits synthesis of thyroid hormones by decreasing iodine use in manufacture of thyroglobin and iodothyronine; does not affect circulatory T
4
, T
3
Hyperthyroidism, preparation for thyroidectomy, thyrotoxic crisis; thyroid storm when PTU is contraindicated
Pregnancy (D), breastfeeding, hypersensitivity
Precautions:
Infection, bone marrow suppression, hepatic disease, bleeding disorders
Calculator
• Adult:
PO
15 mg/day (mild hyperthyroidism); 30-40 mg/day (moderate to severe); 60 mg/day (severe); maintenance 5-15 mg/day; may be divided
• Child:
PO
0.4 mg/kg/day in divided doses q8hr; continue until euthyroid; maintenance dose 0.2 mg/kg/day in divided doses q8hr, max 30 mg/24 hr; may be divided
• Adult and child:
PO
same as above; iodine may be added × 10 days before surgery
• Adult and child:
PO
same as hyperthyroidism with iodine and propranolol
Available forms:
Tabs 5, 10, 15, 20 mg
•
With meals to decrease GI upset
•
At same time each day to maintain product level
•
Lowest dose that relieves symptoms; discontinue before RAIU
CNS:
Drowsiness, headache, vertigo, fever
, paresthesias, neuritis
ENDO:
Enlarged thyroid
GI:
Nausea, diarrhea, vomiting
,
jaundice, hepatitis,
loss of taste
GU:
Nephritis
HEMA:
Agranulocytosis, leukopenia, thrombocytopenia, hypothrombinemia, lymphadenopathy,
bleeding, vasculitis
INTEG:
Rash, urticaria, pruritus, alopecia, hyperpigmentation
, lupuslike syndrome
MS:
Myalgia, arthralgia, nocturnal muscle cramps
Onset 12-18 hr; duration 36-72 hr; half-life 4-12 hr; excreted in urine, breast milk; crosses placenta
Increase:
bone marrow depression—radiation, antineoplastic agents
Increase:
response to digoxin
Decrease:
effectiveness—amiodarone, potassium iodide
Decrease:
Anticoagulant effect—warfarin
Increase:
PT, AST, ALT, alk phos
•
Hyperthyroidism:
palpitation, nervousness, loss of hair, insomnia, heat intolerance, weight loss, diarrhea
•
Hypothyroidism:
constipation, dry skin, weakness, fatigue, headache, intolerance to cold, weight gain; adjustment may be needed
•
Pulse, B/P, temp
•
I&O ratio; check for edema: puffy hands, feet, periorbits; these indicate hypothyroidism
•
Weight daily; same clothing, scale, time of day
•
T
3
, T
4
, which are increased; serum TSH, which is decreased; free thyroxine index, which is increased if dosage too low; discontinue product 3-4 wk before RAIU
Blood dyscrasias:
CBC, leukopenia, thrombocytopenia, agranulocytosis; if these occur, product should be discontinued and other treatment initiated, may occur at higher doses
•
Hypersensitivity:
rash, enlarged cervical lymph nodes; product may have to be discontinued
•
Hypoprothrombinemia:
bleeding, petechiae, ecchymosis
•
Clinical response:
after 3 wk should include increased weight; decreased T
4
, pulse
Bone marrow suppression:
sore throat, fever, fatigue
•
Storage in light-resistant container
•
Increased fluids to 3-4 L/day unless contraindicated
•
Therapeutic response: weight gain, decreased pulse, decreased T
4
, B/P
•
Not to breastfeed
•
To take pulse daily
•
To report redness, swelling, sore throat, mouth lesions, fever, which indicate blood dyscrasias
•
To keep graph of weight, pulse, mood
•
To avoid OTC products, seafood that contains iodine, other iodine products
•
Not to discontinue product abruptly because thyroid crisis may occur; stress patient response
•
That response may take several months if thyroid is large
•
Symptoms and signs of overdose:
periorbital edema, cold intolerance, mental depression
•
Symptoms of inadequate dose:
tachycardia, diarrhea, fever, irritability
•
To take medication as prescribed; not to skip or double dose
Canada only Side effects:
italics
= common;
bold
= life-threatening Nurse Alert
HIGH ALERTmethotrexate (Rx)
(meth-oh-trex′ate)
Rheumatrex, Trexall
Func. class.:
Antineoplastic-antimetabolite (vesicant)
Chem. class.:
Folic acid antagonist
Do not confuse:
methotrexate
/metolazone/mitoXANtrone
Inhibits an enzyme that reduces folic acid, which is needed for nucleic acid synthesis in all cells; specific to S phase of cell cycle; immunosuppressive
Acute lymphocytic leukemia; in combination for breast, lung, head, neck carcinoma; lymphosarcoma, gestational choriocarcinoma, hydatidiform mole, psoriasis, RA, mycosis fungoides, osteosarcoma
Unlabeled uses:
Burkitt’s lymphoma, bladder or ovarian cancer, carcinomatous meningitis, desmoid tumor, fibromatosis, asthma, active Crohn’s disease, ulcerative colitis, GVHD prophylaxis, ectopic pregnancy, pregnancy termination, psoriatic arthritis, pruritus due to cholestasis or primary biliary cirrhosis, SLE, sarcoidosis
Hypersensitivity, leukopenia (<3500/mm
3
), thrombocytopenia (<100,000/mm
3
), anemia; psoriatic patients with severe renal disease, alcoholism, HIV
Black Box Warning:
Pregnancy (X), hepatic disease
Precautions:
Breastfeeding, children
Black Box Warning:
Renal disease, ascites, diarrhea, exfoliative dermatitis, infection, intrathecal administration, lymphoma, pleural effusion, pulmonary disease, radiation therapy, stomatitis, tumor lysis syndrome, renal impairment
Calculator
• Adult and child:
PO/IM/IV
3.3 mg/m
2
/day × 4-6 wk until remission then 20-30 mg/m
2
PO/IM
weekly in 2 divided doses or 2.5 mg/kg
IV
× 2 wk
• Adult and child:
PO/IM
15-30 mg/day × 5 days then off 1 wk; may repeat
• Adult and child:
12 mg/m
2
INTRATHECALLY
q2-5days until CSF is normal then 1 additional dose, max 15 mg
• Adult:
PO/IM/IV
0.625-2.5 mg/kg/day
• Adult and child:
IV
12 g/m
2
given over 4 hr then leucovorin rescue
• Adult:
PO
5-50 mg q wk or 15-37.5 mg twice weekly;
IV/IM
50 mg q week or 15-37.5 mg twice weekly
• Adult:
PO/IM/IV
10-25 mg/wk or 2.5 mg
PO
q12hr × 3 doses/wk, may increase to 25 mg/wk
• Adult:
IV
40-60 mg/m
2
on day 1 of every 21-28 days with other antineoplastics
• Adult/child:
IV
40 mg/m
2
on days 1 and 15, q21days alone or in combination with bleomycin, CISplatin
• Adult:
PO
25-50 mg/m
2
q7days
• Child:
PO
7.5-30 mg/m
2
q7-14days
• Adult:
PO
7.5 mg/wk or in divided doses of 2.5 mg q12hr × 3 given per wk; max 20 mg/wk
• Child:
PO/IM
10 mg/m
2
/wk
• Adult/adolescent/child:
IV
200 mg/m
2
days 8 and 15 q21days with bleomycin, cyclophosphamide, vinCRIStine, dexamethasone
• Adult:
IV
30 mg/m
2
on days 1, 15, 22 q28days in combination with vinBLAStine, DOXOrubicin, CISplatin (MVAC) regimen
• Adult:
IM
25 mg/wk;
SUBCUT
15 mg/kg/wk × 16 wk
• Adult and child:
IV
15 mg/m
2
on day 1 after transplant then 10 mg/m
2
on days 3, 6, 11
• Adult:
IM
50 mg/m
2
may be used in combination with mifepristone
• Adult:
IM
50 mg/m
2
then intravaginal misoprostol 5-7 days later
• Adult:
PO
5-7.5 mg weekly
Available forms:
Tabs 2.5, 5, 7.5, 10, 15 mg; inj 25 mg/ml; powder for inj 1 g
•
Using chemotherapeutic handling
•
Antiemetic 30-60 min before product
•
Allopurinol or sodium bicarbonate to maintain uric acid levels, alkalinization of urine (pH >7.5), adequate fluids
•
After diluting 5 mg/2 ml of sterile water for inj; give through
Y
-tube or 3-way stopcock
•
Further dilute in D5W, D5NS, NS, prior to infusion check patency of vein, flush with 5-10 ml of D5W, NS, infuse at 4-20 mg/hr or prescribed rate
Leucovorin rescue:
leucovorin calcium within 24 hr of product to prevent tissue damage; check agency policy, continue until methotrexate level <10
−8
m
IV INF intermediate or high dose (500 mg/m
2
over <4 hr or >1 g/m
2
over >4 hr):
confirm WBC >1500/mm
3
, neutrophils >200/mm
3
, platelets >75,000/mm
3
, serum bilirubin <1.2 mg/dl, serum creatinine WNL, SGPT <450 U, creatinine clearance >60 ml/min
Give sodium bicarbonate tabs or IV fluids to prevent precipitation of product at high doses; urine pH should be >7; may need to reduce dosage if BUN 20-30
mg/dl or creatinine is 1.2-2 mg/dl; stop product if BUN >30 mg/dl or creatinine >2 mg/dl
Additive compatibilities:
Cephalothin, cyclophosphamide, cytarabine, fluorouracil, hydrOXYzine, mercaptopurine, ondansetron, sodium bicarbonate, vinCRIStine
Solution compatibilities:
Amino acids, 4.25%/D
25
, D
5
W, sodium bicarbonate 0.05 mol/L, sodium chloride 0.9%
Syringe compatibilities:
Bleomycin, CISplatin, cyclophosphamide, doxapram, DOXOrubicin, fluorouracil, furosemide, heparin, leucovorin, mitoMYcin, vinBLAStine, vinCRIStine
Y-site compatibilities:
Allopurinol, amifostine, amphotericin B cholesteryl, asparaginase, aztreonam, bleomycin, cefepime, cefTRIAXone, cimetidine, CISplatin, cyclophosphamide, cytarabine, DAUNOrubicin, dexchlorpheniramine, diphenhydrAMINE, DOXOrubicin, DOXOrubicin liposome, etoposide, famotidine, filgrastim, fludarabine, fluorouracil, furosemide, gallium, ganciclovir, graniset-ron, heparin, HYDROmorphone, imipenem-cilastatin, leucovorin, LORazepam, melphalan, mesna, methylPREDNISolone, metoclopramide, mitoMYcin, morphine, ondansetron, oxacillin, PACLitaxel, piperacillin/tazobactam, prochlorperazine, ranitidine, sargramostim, teniposide, thiotepa, vinBLAStine, vinCRIStine, vinorelbine
Black Box Warning:
Use preservative-free sol, reconstitute with NS; dose should be drawn into 5- to 10-ml syringe after LP, vol of CSF should be withdrawn equal to vol of methotrexate; allow CSF to flow into syringe and mix, inject over 15-30 sec with bevel of needle upward
CNS:
Dizziness,
seizures, leukoencephalopathy,
headache, confusion,
encephalopathy,
hemiparesis, malaise, fatigue, chills, fever;
arachnoiditis
(intrathecal)
EENT:
Blurred vision, optic neuropathy
GI:
Nausea, vomiting, anorexia, diarrhea, ulcerative stomatitis
,
hepatotoxicity,
cramps, ulcer, gastritis,
GI hemorrhage,
abdominal pain, hematemesis,
hepatic fibrosis, acute toxicity
GU:
Urinary retention,
renal failure,
menstrual irregularities, defective spermatogenesis,
hematuria, azotemia, uric acid nephropathy
HEMA:
Leukopenia, thrombocytopenia, myelosuppression, anemia
INTEG:
Rash, alopecia
, dry skin, urticaria, photosensitivity, folliculitis, vasculitis, petechiae, ecchymosis, acne, alopecia,
severe fatal skin reaction
RESP:
Methotrexate-induced lung disease
SYST:
Sudden death,
Pneumocystis jiroveci
,
tumor lysis syndrome
Not metabolized; excreted in urine (unchanged); crosses placenta, blood-brain barrier; 50% plasma protein bound; terminal half-life 10-12 hr
PO:
Readily absorbed
PO/IM/IV:
Onset, duration unknown
IT:
Onset, peak, duration unknown
Do not use with proton pump inhibitors
Increase:
toxicity—salicylates, sulfa products, other antineoplastics, radiation, alcohol, probenecid, NSAIDs, phenylbutazone, theophylline, penicillins
Increase:
hypoprothrombinemia—oral anticoagulants
Increase:
hepatitis—acitretin, avoid concurrent use
Decrease:
effect of oral digoxin, vaccines, phenytoin, fosphenytoin
Decrease:
effect of methotrexate—folic acid supplements
•
Make sure product is taken weekly in RA, JRA
Black Box Warning:
Infection:
those with active infections should be treated for infection before product use; monitor temperature, fever may indicate beginning of infection
•
Make sure drug-drug interacting products are discontinued before therapy, and do not resume until methotrexate level is safe
CBC, differential, platelet count weekly; avoid use until WBC is >1500/mm
3
or platelet count is >75,000/mm
3
, neutrophils >200/mm
3
; notify prescriber; WBC, platelet nadirs occur on day 7; monitor
Black Box Warning:
Renal disease:
avoid use in renal failure, BUN, serum uric acid, urine CCr, electrolytes before, during therapy; I&O ratio; report fall in urine output to <30 ml/hr
•
Bleeding time, coagulation time during treatment; bleeding: hematuria, guaiac, bruising, or petechiae in mucosa or orifices
•
Effects of alopecia on body image; discuss feelings about body changes
Black Box Warning:
Pulmonary toxicity:
those with ascites or pleural effusion at greater risk for toxicity; fluid should be removed before treatment; monitor plasma methotrexate levels
Black Box Warning:
Tumor lysis syndrome:
hyperkalemia, hyperphosphatemia, hyperuricemia, hypocalcemia, decreased urine output; use aggressive hydration, allopurinol to correct severe electrolyte imbalances, renal toxicity
Black Box Warning:
Hepatotoxicity:
jaundiced skin and sclera, dark urine, clay-colored stools, pruritus, abdominal pain, fever, diarrhea, hepatic studies before and during therapy: bilirubin, alk phos, AST, ALT; liver biopsy should be done before start of therapy (psoriasis)
•
Monitor methotrexate levels, adjust leucovorin dose based on level
•
Buccal cavity for dryness, sores, ulceration, white patches, oral pain, bleeding, dysphagia
Black Box Warning:
Serious skin reaction:
Stevens-Johnson syndrome, exfoliate dermatitis, skin necrosis, erythema multiform may occur within days of receiving product by any route, product should be discontinued
•
Strokelike encephalopathy:
common in high-dose therapy; assess for confusion, hemiparesis, seizures, coma; usually transient
•
Rheumatoid arthritis:
ROM, pain, joint swelling before, during treatment
•
Psoriasis:
skin lesions before, during treatment
•
Increased fluid intake to 2-3 L/day to prevent urate deposits, calculi formation unless contraindicated
•
Rinsing of mouth tid-qid with water, club soda; brushing of teeth bid-tid with soft brush or cotton-tipped applicators for stomatitis; use unwaxed dental floss
•
Storage in tightly closed container in cool environment; store injection, powder for inj in dark, dry area
•
Therapeutic response: decreased tumor size, spread of malignancy; decreased joint inflammation, pain in RA
Black Box Warning:
To report any complaints, side effects to nurse or prescriber: black tarry stools, chills, fever, sore throat, bleeding, bruising, cough, SOB, dark or bloody urine, seizures
•
That hair may be lost during treatment; that wig or hairpiece may make patient feel better; that new hair may be different in color, texture (alopecia rare)
•
To avoid foods with citric acid, hot or rough texture if stomatitis is present
•
To report stomatitis and any bleeding, white spots, ulcerations in mouth to prescriber; to examine mouth daily; to report symptoms to nurse; to use good oral hygiene
Black Box Warning:
That contraceptive measures are recommended during therapy and for at least 8 wk after cessation of therapy for women and men; to discontinue breastfeeding; that toxicity to infant may occur; pregnancy (X)
•
To drink 10-12 glasses of fluid/day
•
To avoid alcohol, salicylates, live vaccines
•
To avoid use of razors, commercial mouthwash
•
To use sunblock to prevent burns
•
To use good dental care, to prevent overgrowth of infection in the mouth
•
How to use this product with leucovorin rescue
•
To continue leucovorin until told it is safe to stop
•
To report CNS symptoms, vision changes
•
To report fever, other symptoms of infection
•
To report decreased urine output
