Read Mosby's 2014 Nursing Drug Reference Online
Authors: Linda Skidmore-Roth
(riff′ah-pen-teen)
Priftin
Func. class.:
Antitubercular
Chem. class.:
Rifamycin derivative
Inhibits DNA-dependent polymerase, decreases tubercle bacilli replication
Pulmonary TB; must be used with at least one other antitubercular agent
Hypersensitivity to rifamycins, porphyria
Precautions:
Pregnancy (C), breastfeeding, children <12 yr, geriatric patients, hepatic disease, blood dyscrasias, HIV
• 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
• Adult:
PO
600 mg q wk × 4 mo in combination with isoniazid or other appropriate antitubercular product
Available forms:
Tabs 150 mg
•
May give with food for GI upset, use other products for TB
•
Antiemetic if vomiting occurs
•
After C&S completed; monthly to detect resistance
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
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
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
Increase:
absorption with food
Increase:
LFTs, platelets
Decrease:
Hgb, WBC
Interference:
folate level, vit B
12
•
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
•
Therapeutic response: decreased symptoms of TB, culture negative
•
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
(rif-ax′i-min)
Xifaxan
Func. class.:
Antiinfective—miscellaneous
Chem. class.:
Analog of rifampin
Do not confuse:
rifaximin
/rifampin
Binds to bacterial-DNA–dependent RNA polymerase, thereby inhibiting bacterial RNA synthesis
Traveler’s diarrhea in those ≥12 yr caused by
E. coli
, hepatic encephalopathy
Unlabeled uses:
Crohn’s disease, diverticulitis
Hypersensitivity to product, rifamycins; diarrhea with fever, blood in stool
Precautions:
Pregnancy (C), breastfeeding, children, geriatric patients
• Adult and child ≥12 yr:
PO
200 mg tid × 3 days without regard to meals
• Adult:
PO
550 mg bid
• Adult:
PO
200 mg tid × 16 wk
• Adult:
PO
400 mg bid with mesalamine 800 mg tid × 7 days then 7 days/mo
• Adult:
PO
550 mg tid × 14 day
Available forms:
Tabs 200, 550 mg
•
Without regard to food
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
Half-life 1.8-4.5 hr, excreted in feces, peak 1-4 hr
•
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
•
Therapeutic response: absence of infection
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