Mosby's 2014 Nursing Drug Reference (352 page)

BOOK: Mosby's 2014 Nursing Drug Reference
7.19Mb size Format: txt, pdf, ePub
rifapentine (Rx)

(riff′ah-pen-teen)

Priftin

Func. class.:
Antitubercular

Chem. class.:
Rifamycin derivative

ACTION:

Inhibits DNA-dependent polymerase, decreases tubercle bacilli replication

USES:

Pulmonary TB; must be used with at least one other antitubercular agent

CONTRAINDICATIONS:

Hypersensitivity to rifamycins, porphyria

Precautions:
Pregnancy (C), breastfeeding, children <12 yr, geriatric patients, hepatic disease, blood dyscrasias, HIV

DOSAGE AND ROUTES
Calculator
Intensive phase

• Adult:
PO
600 mg (four 150-mg tabs) 2×/wk with an interval of 72 hr between doses × 2 mo; must be given with at least 1 other antitubercular agent

Continuation phase

• Adult:
PO
600 mg q wk × 4 mo in combination with isoniazid or other appropriate antitubercular product

Available forms:
Tabs 150 mg

Administer:

• 
May give with food for GI upset, use other products for TB

• 
Antiemetic if vomiting occurs

• 
After C&S completed; monthly to detect resistance

SIDE EFFECTS

CNS:
Headache, fatigue, anxiety, dizziness

EENT:
Visual disturbances

GI:
Nausea, vomiting, anorexia, diarrhea
, bilirubinemia, hepatitis, increased ALT, AST,
heartburn
,
pancreatitis, pseudomembranous colitis

GU:
Hematuria,
pyuria, proteinuria, urinary casts, urine discoloration

HEMA:
Thrombocytopenia, leukopenia, neutropenia, lymphopenia,
anemia,
leukocytosis,
purpura, hematoma

INTEG:
Rash, pruritus, urticaria, acne

MISC:
Increased B/P

MS:
Gout, arthrosis

PHARMACOKINETICS

Peak 5-6 hr; half-life 13 hr; metabolized in liver (active/inactive metabolites); excreted in urine, feces, breast milk; protein binding 97%; steady state 10 days; CYP450 3A4, 2C8/9 inducer

INTERACTIONS

 
Do not use with protease inhibitors

Decrease:
action of amitriptyline, anticoagulants, antidiabetics, barbiturates, β-blockers, chloramphenicol, clarithromycin, clofibrate, corticosteroids, cycloSPORINE, dapsone, delavirdine, diazepam, digoxin, diltiazem, disopyramide, doxycycline, fentaNYL, fluconazole, haloperidol, indinavir, itraconazole, ketoconazole, methadone, mexiletine, nelfinavir, NIFEdipine, nortriptyline, oral contraceptives, phenothiazines, phenytoin, progestins, quiNIDine, quiNINE, ritonavir, saquinavir, sildenafil, tacrolimus, theophylline, thyroid preparations, tocainide, verapamil, warfarin, zidovudine

Drug/Food

Increase:
absorption with food

Drug/Lab Test

Increase:
LFTs, platelets

Decrease:
Hgb, WBC

Interference:
folate level, vit B
12

NURSING CONSIDERATIONS
Assess:

• 
Baselines of CBC, AST, ALT, bilirubin, platelets

• 
Infection:
sputum culture, lung sounds

• 
Signs of anemia: Hct, Hgb, fatigue

• 
Hepatic studies monthly: ALT, AST, bilirubin; decreased appetite, jaundice, dark urine, fatigue

• 
Renal status monthly: BUN, creatinine, output, specific gravity, urinalysis

 
Pseudomembranous colitis:
diarrhea, fever, abdominal pain/cramping, bloody diarrhea; discontinue if present, notify prescriber

Evaluate:

• 
Therapeutic response: decreased symptoms of TB, culture negative

Teach patient/family:

• 
That compliance with dosage schedule, duration necessary

• 
That scheduled appointments must be kept because relapse may occur

• 
That urine, feces, saliva, sputum, sweat, tears may be colored red-orange; that soft contact lenses, dentures may be permanently stained

 
To use alternative method of contraception; that oral contraceptive action may be decreased; to notify prescriber if pregnancy planned, suspected; to avoid breastfeeding

 
To report flulike symptoms: excessive fatigue, anorexia, vomiting, sore throat; unusual bleeding, yellowish discoloration of skin, eyes; diarrhea with pus, mucous, blood

Canada only   Side effects:
italics
= common;
bold
= life-threatening   
Nurse Alert

rifaximin (Rx)

(rif-ax′i-min)

Xifaxan

Func. class.:
Antiinfective—miscellaneous

Chem. class.:
Analog of rifampin

Do not confuse:
rifaximin
/rifampin

ACTION:

Binds to bacterial-DNA–dependent RNA polymerase, thereby inhibiting bacterial RNA synthesis

USES:

Traveler’s diarrhea in those ≥12 yr caused by
E. coli
, hepatic encephalopathy

Unlabeled uses:
Crohn’s disease, diverticulitis

CONTRAINDICATIONS:

Hypersensitivity to product, rifamycins; diarrhea with fever, blood in stool

Precautions:
Pregnancy (C), breastfeeding, children, geriatric patients

DOSAGE AND ROUTES
Calculator
Traveler’s diarrhea

• Adult and child ≥12 yr:
PO
200 mg tid × 3 days without regard to meals

Hepatic encephalopathy

• Adult:
PO
550 mg bid

Crohn’s disease (unlabeled)

• Adult:
PO
200 mg tid × 16 wk

Diverticulitis (unlabeled)

• Adult:
PO
400 mg bid with mesalamine 800 mg tid × 7 days then 7 days/mo

Irritable bowel syndrome (unlabeled)

• Adult:
PO
550 mg tid × 14 day

Available forms:
Tabs 200, 550 mg

Administer:

• 
Without regard to food

SIDE EFFECTS

CNS:
Abnormal dreams, dizziness, insomnia

CV:
Hypotension, chest pain, peripheral edema

GI:
Abdominal pain, constipation, defecation urgency, flatulence, nausea, rectal tenesmus
, vomiting, ascites,
pseudomembranous colitis

MISC:
Headache, pyrexia
, motion sickness, tinnitus, rash, photosensitivity,
exfoliative dermatitis

MS:
Arthralgia

RESP:
Dyspnea, cough, pharyngitis

PHARMACOKINETICS

Half-life 1.8-4.5 hr, excreted in feces, peak 1-4 hr

NURSING CONSIDERATIONS
Assess:

• 
GI symptoms: amount, character of diarrhea; abdominal pain, nausea, vomiting, blood in stool, do not use in those with blood in stool, increased temperature with diarrhea

 
Overgrowth of infection, pseudomembranous colitis

Evaluate:

• 
Therapeutic response: absence of infection

Teach patient/family:

 
To discontinue rifaximin, notify prescriber if diarrhea persists >24-48 hr, if diarrhea worsens, or if blood in stools and fever present

• 
To avoid hazardous activities if dizziness occurs

• 
To notify prescriber if pregnancy planned, suspected

• 
That headache, rash, insomnia, abnormal dreams, tinnitus may occur

• 
To take without regard to food

• 
To take as directed, consume all of the product prescribed

Other books

The Last Girl by Joe Hart
The Days of the Rainbow by Antonio Skarmeta
So Much to Live For by Lurlene McDaniel
The Pastor's Heart by Future, Desiree
Oceánico by Greg Egan
The Clockwork Teddy by John J. Lamb