Mosby's 2014 Nursing Drug Reference (30 page)

• Adult and child >9 yr:
PO
200 mg/day in single dose or divided bid

• Geriatric:
PO
No more than 100 mg/day

• Child 1-8 yr:
PO
4.4-8.8 mg/kg/day divided bid-tid, max 150 mg/day

• Adult: PO
100 mg bid up to 400 mg/day in EPS; give for 1 wk then 100 mg as needed up to 400 mg for parkinsonism

• Adult: PO
CCr 30-50 ml/min 200 mg 1st day then 100 mg/day; CCr 15-29 ml/min 100 mg 1st day then 100 mg on alternate days; CCr 15 ml/min reduce dose and interval to 200 mg q7days

• Adult: PO
200 mg/day or 100 mg bid

• Adult: PO
100 mg bid × 3 wk

• 
Prophylaxis:
before exposure to influenza; continue for 10 days after contact;
treatment:
initiate within 24-48 hr of onset of symptoms, continue for 24-48 hr after symptoms disappear

• 
After meals for better absorption to decrease GI symptoms; at least 4 hr before bedtime to prevent insomnia

• 
In divided doses to prevent CNS disturbances: headache, dizziness, fatigue, drowsiness

Increase:
anticholinergic response—atropine, other anticholinergics

Increase:
CNS stimulation—CNS stimulants

Decrease:
amantadine effect—metoclopramide, phenothiazines

Decrease:
renal excretion of amantadine—triamterene, hydrochlorothiazide

Decrease:
effect—S/B H1N1 influenza A virus vaccine; avoid use 2 wk before or 48 hr after amantadine

Increase:
BUN, creatinine, alk phos, CK, LDH, bilirubin, AST, ALT, GGT

• 
Mental status: may cause increased psychiatric disorders especially in the elderly

• 
CHF
(weight gain, jugular venous distention, dyspnea, crackles)

• 
Skin eruptions, photosensitivity after administration of product

• 
Reaction to each medication

• 
Signs of infection

• 
Livedo reticularis:
mottling of the skin, usually red; edema; itching in lower extremities

• 
Parkinson’s disease:
gait, tremors, akinesia, rigidity, may be effective if anticholinergics have not been effective

 
Toxicity:
confusion, behavioral changes, hypotension, seizures

• 
Storage in tight, dry container

• 
Therapeutic response: absence of fever, malaise, cough, dyspnea with infection; tremors, shuffling gait with Parkinson’s disease

• 
To change body position slowly to prevent orthostatic hypotension

• 
About aspects of product therapy: to report dyspnea, weight gain, dizziness, poor concentration, dysuria, complex sleep behaviors

• 
To avoid hazardous activities if dizziness, blurred vision occurs

• 
To take product exactly as prescribed; parkinsonian crisis may occur if product is discontinued abruptly; not to double dose; if a dose is missed, not to take within 4 hr of next dose; caps may be opened and mixed with food

• 
To avoid alcohol

• Adult: PO
5 mg/day; may increase to 10 mg/day if needed

• Adult: PO
Discontinue if AST/ALT >5× ULN, or if elevations are accompanied by bilirubin >2× ULN, or other signs of liver dysfunction

• 
Do not break, crush, chew tabs

• 
Daily with a full glass of water without regard to food

• 
Do not discontinue abruptly

• 
Only those facilities enrolled in the LEAP program (866-664-5327) may administer this product

Increase:
hypotension—other antihypertensives, diuretics, MAOIs

Increase:
ambrisentan—CYP3A4 inhibitors (amprenavir, aprepitant, atazanavir, clarithromycin, conivaptan, cycloSPORINE, dalfopristin, danazol, darunavir, erythromycin, estradiol, imatinib, itraconazole, ketoconazole, nefazodone, nelfinavir, propoxyphene, quinupristin, ritonavir, RU-486, saquinavir, tamoxifen, telithromycin, troleandomycin, zafirlukast); CYP2C19/CYP3A4 (chloramphenicol, delavirdine, fluconazole, fluvoxaMINE, isoniazid, voriconazole)

Decrease:
ambrisentan—CYP3A4 inducers (carBAMazepine, PHENobarbital, phenytoin, rifampin)

Decrease:
ambrisentan absorption—mefloquine, niCARdipine, propafenone, quiNIDine, ranolazine, tacrolimus, testosterone

• 
Need for ambrisentan dosage change: St. John’s wort, ephedra (ma huang)

• 
Avoid use with grapefruit products

Increase:
LFTs, bilirubin

Decrease:
Hct, Hgb

• 
Pulmonary status:
improvement in breathing, ability to exercise; pulmonary edema that may indicate veno-occlusive disease

• 
Blood studies: CBC with differential; Hct, Hgb may be decreased

• 
Liver function tests: AST, ALT, bilirubin

Black Box Warning:

Assess pregnancy status before giving this product; pregnancy category X

• 
Hepatotoxicity: nausea, vomiting, abdominal pain/cramping, jaundice, anorexia, itching

• 
Storage in tight container at room temp

• 
Therapeutic response: decrease in B/P; decreased shortness of breath

• 
The importance of complying with dosage schedule even if feeling better

Black Box Warning:

To notify if pregnancy is planned or suspected (if pregnant, product will need to be discontinued, pregnancy test done monthly); to use 2 contraception methods while taking this product

• 
Not to use OTC products including herbs, supplements unless approved by prescriber

• 
To report to prescriber immediately: dizziness, faintness, chest pain, palpitations, uneven or rapid heart rate, headache, edema, weight gain

• 
To report hepatic dysfunction: nausea/vomiting, anorexia, fatigue, jaundice, right upper quadrant abdominal pain, itching, fever, malaise