Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
(a-man′ta-deen)
Func. class.:
Antiviral, antiparkinsonian agent
Chem. class.:
Tricyclic amine
Do not confuse:
amantadine
/ranitidine/rimantidine
Prevents uncoating of nucleic acid in viral cell, thereby preventing penetration of virus to host; causes release of DOPamine from neurons
Prophylaxis or treatment of influenza type A, EPS, parkinsonism, Parkinson’s disease
Unlabeled uses:
Neuroleptic malignant syndrome, MS-associated fatigue
Hypersensitivity, breastfeeding, children <1 eczematic rash
Precautions:
Pregnancy (C), geriatric patients, epilepsy, CHF, orthostatic hypotension, psychiatric disorders, renal/hepatic disease, peripheral edema
• 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
Available forms:
Caps 100 mg; oral sol 50 mg/5 ml; tab 100 mg
•
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
CNS:
Headache, dizziness
, drowsiness, fatigue,
anxiety
, psychosis,
depression, hallucinations
, tremors,
seizures,
confusion,
insomnia
CV:
Orthostatic hypotension
,
CHF
EENT:
Blurred vision
GI:
Nausea, vomiting
, constipation, dry mouth, anorexia
GU:
Frequency, retention
HEMA:
Leukopenia, agranulocytosis
INTEG:
Photosensitivity, dermatitis, livedo reticularis
PO:
Onset 48 hr, peak 1-4 hr, half-life 24 hr, not metabolized, excreted in urine (90%) unchanged, crosses placenta, excreted in breast milk
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
Withdraw product, maintain airway, administer EPINEPHrine, aminophylline, O
2
, IV corticosteroids, physostigmine
Canada only Side effects:
italics
= common;
bold
= life-threatening
Nurse Alert
(am-bri-sen′tan)
Letairis
Func. class.:
Antihypertensive
Chem class.:
Vasodilator/endothelin receptor antagonist
Endothelin-A receptor antagonist; endothelin-A is vasoconstrictor
Pulmonary arterial hypertension, alone or in combination with other antihypertensives
Breastfeeding, hypersensitivity, idiopathic pulmonary fibrosis (IPF)
Black Box Warning:
Pregnancy (X)
Precautions:
Children, females, geriatric patients, hepatitis, anemia, heart failure, jaundice, peripheral edema, hepatic disease
• 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
Available forms:
Tabs 5, 10 mg
•
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
CNS:
Headache
, fever, flushing, fatigue
CV:
Orthostatic hypotension, hypotension,
peripheral edema
, palpitations
EENT:
Sinusitis, rhinitis
GI:
Abdominal pain, constipation, anorexia,
hepatotoxicity
GU:
Decreased sperm counts
HEMA:
Anemia
INTEG:
Rash,
angioedema
RESP:
Pharyngitis, dyspnea,
pulmonary edema, veno-occlusive disease (VOD)
Rapidly absorbed, peak 2 hr, protein binding 99%, metabolized by CYP3A4, CYP2C19, terminal half-life 15 hr, effective half-life 9 hr
•
Possibly increase ambrisentan: cimetidine, clopidogrel, efavirenz, felbamate, fluoxetine, modafinil, oxcarbazepine, ticlopidine
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