Body Weight	Induction	Maintenance
40 kg and over	900 mg weekly × 4 doses	1,200 mg wk 5, then 1,200 mg q2wks
30–39 kg	600 mg weekly × 2 doses	900 mg wk 3, then 900 mg q2wks
20–29 kg	600 mg weekly × 2 doses	600 mg wk 3, then 600 mg q2wks
10–19 kg	600 mg weekly × 1 dose	300 mg wk 2, then 300 mg q2wks
5–9 kg	300 mg weekly × 1 dose	300 mg wk 2, then 300 mg q3wks

Side effects

Frequent (44%–23%): Headache, pharyngitis. Occasional (19%–12%): Back pain, nausea, cough, fatigue. Rare (7%): Constipation, myalgia, sinusitis, herpes simplex infection, extremity pain, influenza-like symptoms.

Adverse effects/toxic reactions

Eculizumab increases susceptibility to serious meningococcal infections (septicemia, meningitis), encapsulated bacteria. Pts who discontinue treatment may be at increased risk for serious hemolysis.

Nursing considerations

Baseline assessment

Obtain baseline laboratory studies. Vaccinate pts with meningococcal vaccine at least 2 wks prior to receiving first dose of eculizumab.

Intervention/evaluation

Observe for infusion site reaction. Monitor CBC, LDH, AST, urinalysis results.Monitor for early signs of meningococcal infection (moderate to severe headache with nausea or vomiting; moderate to severe headache and fever; moderate to severe headache with stiff neck or stiff back; fever 103°F or higher; fever with rash, confusion, severe myalgia with flu-like symptoms, photosensitivity).

Patient/ family teaching

• Vaccination may not prevent meningococcal infection.

efavirenz

e-fav-ir-enz

(Sustiva)

Fixed combination(s)

Atripla: efavirenz/emtricitabine (an antiretroviral)/tenofovir (an antiretroviral): 600 mg/200 mg/300 mg.

classification

PHARMACOTHERAPEUTIC: Nonnucleoside reverse transcriptase inhibitor. CLINICAL: Antiretroviral (see pp. 69C, 119C).

Action

Inhibits activity of HIV-1 reverse transcriptase. Therapeutic Effect: Interrupts HIV replication, slowing progression of HIV infection.

Pharmacokinetics

Rapidly absorbed after PO administration. Protein binding: 99%. Metabolized in liver. Eliminated in feces (16%–61%), urine (14%–34%). Half-life: 40–55 hrs.

Uses

Treatment of HIV infection in combination with at least two other appropriate antiretroviral agents in adults and children 3 mos and older.

Precautions

Contraindications: Concurrent use with bepridil, ergot derivatives, midazolam, St. John’s wort, triazolam. Cautions: History of mental illness, seizures, suspected hepatitis B or C, substance abuse, hepatic impairment (class A).

Lifespan considerations

Pregnancy/Lactation: Breastfeeding not recommended. Pregnancy Category C. Children: Safety and efficacy not established in those younger than 3 yrs; may have increased incidence of rash. Elderly: No age-related precautions noted.

Interactions

DRUG: Ergot derivatives, midazolam, triazolam may cause serious or life-threatening reactions (cardiac arrhythmias, prolonged sedation, respiratory depression). Decreases plasma concentrations of amprenavir, atazanavir, boceprevir, telaprevir, indinavir, saquinavir. Increases plasma concentrations of ritonavir. CYP3A4 inducers (e.g., phenobarbital, rifabutin, rifampin) decrease concentration/effect. May alter warfarin plasma concentration. HERBAL: St. John’s wort may decrease concentration/effect. FOOD: High-fat meals may increase drug absorption. LAB VALUES: May produce false-positive urine test results for cannabinoid. May increase serum AST, ALT. May decrease neutrophils.

Availability (Rx)

Capsules: 50 mg, 200 mg.

Tablets: 600 mg.

Administration/handling

PO

• Give with water at bedtime (decreases CNS adverse effects). • Avoid high-fat meals (may increase absorption) • Capsules may be opened and added to small amount of food/liquid. Administer within 30 min. • Do not break, cut, crush, or divide tablets.

Indications/routes/dosage

HIV infection (in combination with other antiretrovirals)

PO: ADULTS, ELDERLY, CHILDREN WEIGHING 40 KG OR MORE: 600 mg once a day at bedtime. CHILDREN WEIGHING 32.5 KG–LESS THAN 40 KG: 400 mg once a day. CHILDREN WEIGHING 25 KG–LESS THAN 32.5 KG: 350 mg once a day. CHILDREN WEIGHING 20 KG–LESS THAN 25 KG: 300 mg once a day. CHILDREN WEIGHING 15 KG–LESS THAN 20 KG: 250 mg once a day. CHILDREN WEIGHING 7.5 KG–LESS THAN 15 KG: 200 mg once a day. CHILDREN WEIGHING 5 KG–LESS THAN 7.5 KG: 150 mg once a day. CHILDREN WEIGHING 3.5 KG–LESS THAN 5 KG: 100 mg once a day.

Dosage: Concurrent rifampin

PO: ONLY IF PT WEIGHS 50 KG OR GREATER: 800 mg once daily.

Dosage: Concurrent voriconazole

PO: Reduce efavirenz to 300 mg once daily; increase voriconazole to 400 mg q12h.

Side effects

Frequent (52%): Mild to severe: Dizziness, vivid dreams, insomnia, confusion, impaired concentration, amnesia, agitation, depersonalization, hallucinations, euphoria. Occasional: Mild to moderate: Maculopapular rash (27%); nausea, fatigue, headache, diarrhea, fever, cough (less than 26%).

Adverse effects/toxic reactions

Serious adverse psychiatric experiences (aggressive reactions, agitation, delusions, emotional lability, mania, neurosis, paranoia, psychosis, suicide) have been reported.

Nursing considerations

Baseline assessment

Offer emotional support. Obtain baseline AST, ALT in pts with history of hepatitis B or C; serum cholesterol or triglycerides before initiating therapy and at intervals during therapy. Obtain history of all prescription and OTC medications (high level of drug interaction).

Intervention/evaluation

Monitor for CNS, psychological symptoms: severe acute depression (including suicidal ideation or attempts), dizziness, impaired concentration, drowsiness, abnormal dreams, insomnia (begins during first or second day of therapy, generally resolves in 2–4 wks). Assess for evidence of rash (common side effect). Monitor hepatic enzyme studies for abnormalities. Assess for headache, nausea, diarrhea.

Patient/family teaching

• Avoid high-fat meals during therapy. • If rash appears, contact physician immediately. • CNS, psychological symptoms occur in more than half of pts (dizziness, impaired concentration, delusions, depression). • Take medication every day as prescribed. • Do not alter dose or discontinue medication without informing physician. • Do not break, chew, crush, or divide tablets. • Avoid tasks that require alertness, motor skills until response to drug is established. • Avoid alcohol. • Efavirenz is not a cure for HIV infection, nor does it reduce risk of transmission to others.

eletriptan

el-e-trip-tan

(Relpax)

classification

PHARMACOTHERAPEUTIC: Serotonin receptor agonist. CLINICAL: Antimigraine (see p. 64C).

Action

Binds selectively to vascular receptors, producing vasoconstrictive effect on cranial blood vessels. Therapeutic Effect: Relieves migraine headache.

Pharmacokinetics

Well absorbed after PO administration. Metabolized by liver. Eliminated in urine. Half-life: 4.4 hrs (increased in hepatic impairment, elderly [older than 65 yrs]).

Uses

Treatment of acute migraine headache with or without aura.

Precautions

Contraindications: Arrhythmias associated with conduction disorders, cerebrovascular syndrome including strokes and transient ischemic attacks (TIAs), coronary artery disease, hemiplegic or basilar migraine, ischemic heart disease, peripheral vascular disease including ischemic bowel disease, severe hepatic impairment, uncontrolled hypertension; use within 24 hrs of treatment with another 5-HT1 agonist, an ergotamine-containing or ergot-type medication such as dihydroergotamine (DHE) or methysergide. Cautions: Mild to moderate renal/hepatic impairment, controlled hypertension, history of CVA.

Lifespan considerations

Pregnancy/Lactation: May decrease possibility of ovulation. Distributed in breast milk. Pregnancy Category C. Children: Safety and efficacy not established in those younger than 18 yrs. Elderly: Increased risk of hypertension in those older than 65 yrs.

Interactions

DRUG: CYP3A4 inhibitors (e.g., clarithromycin, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir) may decrease metabolism. Ergotamine-containing medications may produce vasospastic reaction. HERBAL: None significant. FOOD: None known. LAB VALUES: None known.

Availability (Rx)

Tablets: 20 mg, 40 mg.

Administration/handling

PO

• Do not crush, break film-coated tablets.

Indications/routes/dosage

Acute migraine headache

PO: ADULTS, ELDERLY: 20–40 mg. If headache improves but then returns, dose may be repeated after 2 hrs. Maximum: 80 mg/day.

Side effects

Occasional (6%–5%): Dizziness, drowsiness, asthenia (loss of strength, energy), nausea. Rare (3%–2%): Paresthesia, headache, dry mouth, warm or hot sensation, dyspepsia, dysphagia.

Adverse effects/toxic reactions

Cardiac reactions (ischemia, coronary artery vasospasm, MI), noncardiac vasospasm-related reactions (hemorrhage, CVA) occur rarely, particularly in pts with hypertension, obesity, diabetes, strong family history of coronary artery disease; smokers; males older than 40 yrs; postmenopausal women.

Nursing considerations

Baseline assessment

Question pt regarding onset, location, duration of migraine, possible precipitating symptoms. Obtain baseline B/P for evidence of uncontrolled hypertension (contraindication).

Intervention/evaluation

Assess for relief of migraine headache, potential for photophobia, phonophobia (sound sensitivity), nausea, vomiting.

Patient/family teaching

• Take a single dose as soon as symptoms of an actual migraine attack appear. • Medication is intended to relieve migraine headaches, not to prevent or reduce number of attacks. • Avoid tasks that require alertness, motor skills until response to drug is established. • Immediately report palpitations, pain/tightness in chest/throat, sudden or severe abdominal pain, pain/weakness of extremities.

eltrombopag

el-trom-boe-pag

(Promacta, Revolade )

BLACK BOX ALERT May cause hepatotoxicity. Measure ALT, AST, and bilirubin prior to initiation of eltrombopag, every 2 wks during dose adjustment phase, and monthly following establishment of a stable dose. If bilirubin is elevated, perform fractionation. Discontinue eltrombopag if ALT levels increase to 3 times or greater upper limit of normal and are progressive, persistent for 4 or more wks, accompanied by increased direct bilirubin, clinical symptoms of hepatic injury, or evidence of hepatic decompensation.

classification

PHARMACOTHERAPEUTIC: Thrombopoietin receptor agonist. CLINICAL: Prevents thrombocytopenia.

Action

Interacts with the human thrombopoietin receptor and initiates signaling cascades. Therapeutic Effect: Induces proliferation and differentiation of megakaryocytes from bone marrow progenitor cells.

Pharmacokinetics

Readily absorbed from gastrointestinal tract. Primarily distributed in blood cells. Protein binding: 99%. Extensively metabolized including oxidation, conjugation with glucuronic acid or cysteine. Excreted primarily in feces. Half-life: 26–35 hrs.

Uses

Treatment of thrombocytopenia in pts with chronic immune (idiopathic) thrombocytopenic purpura (ITP) with insufficient response with corticosteroids, immunoglobulins, or splenectomy. Use only in pts who are at increased risk for bleeding; should not be used to normalize platelet counts. Treatment of thrombocytopenia in pts with chronic hepatitis C to allow the initiation and maintenance of interferon-based therapy.

Precautions

Contraindications: None known. Cautions: Preexisting hepatic impairment, renal impairment (any degree), myelodysplastic syndrome (may increase risk for hematologic malignancies). Pts with known risk for thromboembolism, risk for cataracts.

Lifespan considerations

Pregnancy/Lactation: Unknown if distributed in breast milk. Pregnancy Category C. Children: Safety and efficacy not established. Elderly: Use caution due to increased frequency of hepatic, renal, cardiac dysfunction.

Interactions

DRUG: May increase concentration/toxicity of atorvastatin, fluvastatin, methotrexate, nateglinide, pravastatin, repaglinide, rifampin, rosuvastatin. Aluminum, antacids, calcium, iron, magnesium may decrease concentration/effect. HERBAL: None significant. FOOD: Dairy products may decrease concentration/effect. LAB VALUES: May increase serum ALT, AST.

Availability (Rx)

Tablets: 12.5 mg, 25 mg, 50 mg, 75 mg.

Administration/handling

PO

• Give on an empty stomach, either 1 hr before or 2 hrs after eating food. • Give at least 4 hrs before or 4 hrs after ingestion of antacids, food high in calcium or minerals, or calcium-fortified juices.

Indications/routes/dosage

ITP

PO: ADULTS, ELDERLY: Initially, 50 mg once daily (25 mg for pts of East Asian ancestry or moderate to severe hepatic insufficiency). After initiating eltrombopag, adjust dose (25 mg to 75 mg once daily) to achieve and maintain platelet count of 50,000 mm³ or greater as necessary to reduce risk of bleeding. Maximum: 75 mg once daily.

Chronic hepatitis C–associated thrombocytopenia

PO: ADULTS, ELDERLY: 25 mg once daily. Maximum: 100 mg once daily.

Side effects

Frequent (6%–4%): Nausea, vomiting, menorrhagia. Occasional (3%–2%): Myalgia, paresthesia, dyspepsia, ecchymosis, cataract, conjunctival hemorrhage.

Adverse effects/toxic reactions

May cause hepatotoxicity. Increases risk of reticulin fiber deposits within bone marrow (may lead to bone marrow fibrosis). May produce hematologic malignancies. May cause excessive increase in platelets, leading to thrombotic complications.

Nursing considerations

Baseline assessment

Assess CBC and peripheral blood smears; hepatic function tests (ALT, AST, bilirubin) prior to initiating therapy. Examine peripheral blood smear to establish extent of RBC and WBC abnormalities. Obtain baseline ocular examination.

Intervention/evaluation

Monitor CBC, platelet counts, peripheral blood smears, hepatic function tests (ALT, AST, bilirubin) throughout and following discontinuation of eltrombopag. Monitor for signs of cataracts during therapy.

Patient/family teaching

• Lab values will be closely monitored throughout therapy and for at least 4 wks following discontinuation of therapy. • Report any yellowing of the skin or whites of eyes, unusual darkening of the urine, unusual tiredness, pain in right upper stomach area.

emtricitabine

em-tri-sye-ta-bine

(Emtriva)

BLACK BOX ALERT Serious, sometimes fatal, hypersensitivity reaction, lactic acidosis, severe hepatomegaly with steatosis (fatty liver) have occurred. May exacerbate hepatitis B following completion of emtricitabine therapy.

Fixed-combination(s)

Atripla: emtricitabine/efavirenz (an antiretroviral)/tenofovir (an antiretroviral): 200 mg/600 mg/300 mg. Complera: emtricitabine/rilpivirine (an antiretroviral)/tenofovir (an antiretroviral): 200 mg/25 mg/300 mg.

Truvada: emtricitabine/tenofovir (an antiretroviral): 200 mg/300 mg. Stribild: emtricitabine/elvitegravir (an integrase inhibitor)/cobicistat (a pharmacokinetic enhancer)/tenofovir (a nucleotide reverse transcriptase inhibitor): 200 mg/150 mg/150 mg/300 mg.

classification

PHARMACOTHERAPEUTIC: Nucleoside reverse transcriptase inhibitor. CLINICAL: Antiretroviral agent (see p. 117C).

Action

Inhibits HIV-1 reverse transcriptase by incorporating itself into viral DNA, resulting in chain termination. Therapeutic Effect: Impairs HIV replication, slowing progression of HIV infection.

Pharmacokinetics

Rapidly, extensively absorbed from GI tract. Protein binding: less than 4%. Excreted primarily in urine. Half-life: 10 hrs.

Uses

Used in combination with at least two other antiretroviral agents for treatment of HIV-1 infection.

Precautions

Contraindications: None known. Cautions: Renal impairment, history of hepatitis, diabetes.

Lifespan considerations

Pregnancy/Lactation: Breastfeeding not recommended. Pregnancy Category B. Children: Safety and efficacy not established. Elderly: Age-related renal impairment may require dosage adjustment.

Interactions

DRUG: None known. HERBAL: None significant. FOOD: None known. LAB VALUES: May increase serum amylase, lipase, ALT, AST, triglycerides. May alter serum glucose.

Availability (Rx)

Capsules: 200 mg. Oral Solution: 10 mg/ml.

Administration/handling

PO

• Give without regard to food.

Indications/routes/dosage

HIV

Capsules

PO: ADULTS, ELDERLY, CHILDREN 3 MOS–17 YRS, WEIGHING MORE THAN 33 KG: 200 mg once daily.

Oral solution

PO: ADULTS, ELDERLY: 240 mg once daily. CHILDREN 3 MOS–17 YRS WEIGHING MORE THAN 33 KG: 6 mg/kg once daily. Maximum: 240 mg once daily. CHILDREN 0–3 MOS: 3 mg/kg/day.

Dosage in renal impairment

Creatinine Clearance	Capsule	Oral Solution
30–49 ml/min	200 mg q48h	120 mg q24h
15–29 ml/min	200 mg q72h	80 mg q24h
Less than 15 ml/min; hemodialysis pts	200 mg q96h	60 mg q24h (administer after dialysis)