Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
Mosby's 2014 Nursing Drug Reference (330 page)
Canada only Side effects:
italics
= common;
bold
= life-threatening 
Nurse Alert
(pri′mi-done)
Mysoline, Sertan
Func. class.:
Anticonvulsant
Chem. class.:
Barbiturate derivative
Raises seizure threshold by conversion of product to PHENobarbital, decreases neuron firing
Generalized tonic-clonic (grand mal), complex seizures
Unlabeled uses:
Benign familial tremor (essential tremor)
Pregnancy (D), breastfeeding, hypersensitivity, porphyria, hepatic encephalopathy
Precautions:
Hyperactive children, COPD, renal/hepatic disease, suicidal ideation/behavior
Calculator
• Adult and child
>
8 yr:
PO
125-250 mg at bedtime, increase by 125-250 mg/day q3-7days, usual dose 750-1500 mg/day in 3-4 divided doses, max 2 g/day in divided doses
• Child
<
8 yr:
PO
50-125 mg at bedtime, increase by 50-125 mg/day q3-7days, usual dose 10-25 mg/kg/day in 3-4 divided doses
• Neonate:
PO
12-20 mg/kg/day in 2-4 divided doses, start at lower dose and titrate
• Adult:
PO
50-62.5 mg, increase as tolerated up to 750 mg/day in 3 divided doses
• Adult:
PO
CCr 10-50 ml/min, increase interval between doses to 8-12 hr; CCr <10 ml/min, increase interval to 12-24 hr
Available forms:
Tabs 50, 250 mg; susp 250 mg/5 ml; chew tabs 125 mg
•
After shaking liquid susp well
•
With food for GI upset
•
Tablets crushed and mixed with food or fluid for swallowing difficulties
•
Avoid use with CNS depressants
CNS:
Stimulation, drowsiness
, irritability, psychosis, ataxia, vertigo, fatigue, emotional disturbances, mood changes, paranoia,
suicidal ideation
EENT:
Diplopia, nystagmus, edema of eyelids
GI:
Nausea, vomiting, anorexia
,
hepatitis
GU:
Impotence
HEMA:
Thrombocytopenia, leukopenia, neutropenia, eosinophilia, megaloblastic anemia,
decreased serum folate level, lymphadenopathy
INTEG:
Rash
, edema, alopecia, lupuslike syndrome
PO:
Peak 4 hr; metabolized in liver; excreted by kidneys, in breast milk; half-life 10-12 hr (primidone)
•
Primidone levels decreased by acetaZOLAMIDE, succinimides
•
May decrease effect of oral contraceptives, acebutolol, metoprolol, propranolol, tricyclics, phenothiazines, lamoTRIgine, estrogens, non-oral combination contraceptives, progestins
Increase:
primidone levels—alcohol, heparin, CNS depressants, isoniazid, nicotinamide, MAOIs
Increase:
toxicity—CYP3A4 inhibitors (aprepitant, antiretroviral protease inhibitors, delavirdine, fluconazole, imatinib, voriconazole)
Decrease:
primidone effect—CYP3A4 inducers (barbiturates, carBAMazepine, efavirenz, phenytoins, nevirapine)
•
Avoid use with kava, St. John’s wort, valerian
Increase:
effect—ginkgo
Decrease:
effect—ginseng, santonica
•
Seizures:
location, duration, type; folic acid deficiency; fatigue, weakness, neuropathy, depression
•
Product level: therapeutic level 5-15 mcg/ml; CBC, LFTs should be obtained q6mo
Mental status: mood, sensorium, affect, memory (long, short), suicidal thoughts/behaviors
•
Respiratory depression, wheezing
•
Blood dyscrasias: fever, sore throat, bruising, rash, jaundice
•
Therapeutic response: decreased seizures
•
Not to withdraw product quickly because withdrawal symptoms may occur
•
To avoid hazardous activities until stabilized on product because drowsiness, dizziness may occur
•
To carry emergency ID with condition, medication listed
•
To recognize signs of blood dyscrasias; about when to notify prescriber
•
To avoid alcohol
•
Contraception:
Use additional contraceptive during and for 1 mo after therapy, contraceptive may be reduced
Canada only Side effects:
italics
= common;
bold
= life-threatening Nurse Alert
(proe-ben′e-sid)
Func. class.:
Uricosuric, antigout agent
Chem. class.:
Sulfonamide derivative
Inhibits tubular reabsorption of urates, with increased excretion of uric acids
Hyperuricemia in gout, gouty arthritis, adjunct to penicillin treatment
Hypersensitivity, severe renal/hepatic disease, CCr <50 mg/min, history of uric acid calculus
Precautions:
Pregnancy (C), children <2 yr, sulfonamide hypersensitivity, pepticular
Calculator
• Adult/adolescent >15 yr, >50 kg (110 lb):
PO
500 mg qid
• Adult:
PO 250 mg bid for 1 wk, then 500 mg bid, max 2 g/day; maintenance 500 mg/day × 6 mo
• Adult and adolescent
>
50 kg:
PO
500 mg qid
• Child
<
50 kg:
PO
25 mg/kg, then 40 mg/kg in divided doses qid
•
Avoid use if CCr <50 ml/min
Available forms:
Tabs 500 mg
•
After meals or with milk if GI symptoms occur
•
Increase fluid intake to 2-3 L/day to prevent urinary calculi
CNS:
Drowsiness, headache, flushing
CV:
Bradycardia
GI:
Gastric irritation, nausea, vomiting, anorexia
,
hepatic necrosis
GU:
Glycosuria, thirst, frequency,
nephrotic syndrome
INTEG:
Rash, dermatitis, pruritus, fever
META:
Acidosis, hypokalemia, hyperchloremia
, hyperglycemia
RESP:
Apnea,
irregular respirations
Peak 2-4 hr, duration 8 hr, half-life 5-8 hr; metabolized by liver; excreted in urine
Increase:
effect of acyclovir, barbiturates, allopurinol, benzodiazepines, dyphylline, zidovudine, cephalosporins, penicillins, sulfonamides
Increase:
toxicity—sulfa products, dapsone, clofibrate, indomethacin, rifampin, naproxen, methotrexate
Decrease:
action of probenecid—salicylates
Increase:
theophylline levels
•
Uric acid levels (3-7 mg/dl); mobility, joint pain, swelling
•
Respiratory rate, rhythm, depth; notify prescriber of abnormalities
•
Electrolytes; CO
2
before, during treatment
•
Urine pH, output, glucose during beginning treatment
For CNS symptoms: confusion, twitching, hyperreflexia, stimulation, headache; may indicate overdose
•
Therapeutic response: absence of pain, stiffness in joints
•
To avoid OTC preparations (aspirin) unless directed by prescriber; increase water intake, avoid alcohol, caffeine