Names and pronunciation
(fam-cy′clo-veer)
Source page 543
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Individual generic drug information
Extracted information for famciclovir only.
(fam-cy′clo-veer)
Source page 543
Func. class.: Antiviral Func. class.: Antiulcer agent Chem class.: H2-histamine receptor antagonist
Source pages 543, 545
Chem. class.: Guanosine nucleoside
Source page 543
ACTION: Inhibits DNA polymerase F and viral DNA synthesis by conversion of this guanosine nucleoside to penciclovir ACTION: Competitively inhibits hista- mine at histamine H2-receptor site, thus decreasing gastric secretion while pepsin remains at a stable level
Source pages 543, 545
USES: Treatment of acute herpes zoster (shingles), genital herpes; recurrent muco- cutaneous herpes simplex virus (HSV) in patients with HIV; initial episodes of herpes genitalis; herpes labialis in the immuno- compromised, herpes labialis prophylaxis USES: Short-term treatment of duode- nal ulcer, maintenance therapy for duode- nal ulcer, Zollinger-Ellison syndrome, mul- tiple endocrine adenomas, gastric ulcers; gastroesophageal reflux disease, heartburn
Source pages 543, 545
Unlabeled uses: Herpes simplex virus, Varicella infection (chickenpox) in HIV Unlabeled uses: GI disorders in those taking NSAIDs; urticaria; prevention of stress ulcers, aspiration pneumonitis
Source pages 543, 545
Extracted information for famciclovir only.
CONTRAINDICATIONS: Hyper- sensitivity to this product, penciclovir, acyclo- vir, ganciclovir, valacyclovir, valganciclovir Precautions: Pregnancy, breastfeeding, renal disease, lactose intolerance CONTRAINDICATIONS: Hyper- sensitivity Precautions: Pregnancy, breastfeeding, children <12 yr, geriatric patients, severe renal/hepatic disease
Source pages 543, 545
SIDE EFFECTS CNS: Headache, fatigue, dizziness, par- esthesia, somnolence, fever, seizures GI: Nausea, vomiting, diarrhea, constipa- tion, abdominal pain, anorexia GU: Decreased sperm count INTEG: Pruritus, vasculitis MS: Back pain, arthralgia RESP: Pharyngitis, sinusitis SYST: Anaphylaxis SIDE EFFECTS CNS: Headache, dizziness, paresthesia, depression, anxiety, somnolence, insom- nia, fever, seizures in renal disease CV: Dysrhythmias, QT prolongation (impaired renal functioning) EENT: Taste change, tinnitus, orbital edema GI: Constipation, nausea, vomiting, anorexia, cramps, abnormal hepatic enzymes, diarrhea INTEG: Rash, toxic epidermal necrolysis, Stevens-Johnson syndrome MS: Myalgia, arthralgia RESP: Pneumonia
Source pages 544, 546
INTERACTIONS Increase: effect of famciclovir— probenecid Decrease: effect of zoster, varicella virus vaccine Drug/Lab Increase: LFTs INTERACTIONS Decrease: absorption—ketoconazole, itraconazole, cefpodoxime, cefditoren cefuroxime, delaviridine Decrease: famotidine absorption— antacids Drug/Lab Test Increase: LFTs, BUN, creatinine
Source pages 544, 546
Extracted information for famciclovir only.
DOSAGE AND ROUTES Acute herpes zoster (Shingles) • Adult: PO 500 mg q8hr for 7 days Renal dose • Adult: PO CCr 40-59 mL/min, 500 mg q12hr; CCr 20-39 mL/min, 500 mg q24hr; CCr <20 mL/min, 250 mg q24hr Suppression of recurrent herpes simplex • Adult: PO 250 mg q12hr up to 1 yr Renal dose • Adult: PO CCr 20-39 mL/min, 125 mg q12hr × 5 days; CCr <20 mL/min, 125 mg q24hr × 5 days Recurrent herpes labialis (cold sores) • Adult: PO 1500 mg single dose Renal impairment: recurrent herpes labialis • Adult: PO CCr ≥60 mL/min, usual dose; CCr 40-59 mL/min, 750 mg as a single dose; CCr 20-39 mL/min, 500 mg as single dose; CCr <20 mL/min, 250 mg as a single dose; hemodialysis, 250 mg as a single dose following dialysis Recurrent mucocutaneous orolabial genital herpes simplex infections in HIV • Adult: PO 500 mg bid × 7 days Renal impairment: recurrent orolabial or genital herpes in HIV-infected patients • Adult: PO CCr ≥40 mL/min, usual dose; CCr 20-39 mL/min, 500 mg q24hr; CCr <20 mL/min, 250 mg q24hr; hemodialysis, 250 mg following each dialysis Recurrent genital herpes simplex • Adult: PO 1000 mg bid on a single day Renal dose • Adult: PO CCr 40-59 mL/min, 500 mg q12hr × 1 day; CCr 20-39 mL/min, 500 mg as a single dose; CCr <20 mL/min, 250 mg as a single dose Chickenpox (unlabeled) • Adult: PO 500 mg q8hr × 7 days, preferably within 48 hr of onset DOSAGE AND ROUTES Short-term treatment of benign gastric ulcer • Adult/child ≥ 40 kg: PO 40 mg/day at bedtime × 4-8 wk, then 20 mg/day at bedtime if needed (maintenance); IV 20 mg q12hr if unable to take PO • Child 1-16 yr: PO/IV 0.25 mg/kg/dose q12hr, max 40 mg/day Short-term treatment of duodenal ulcer • Adult/child ≥ 40 kg: PO 40 mg at bedtime or 20 mg bid; maintenance 20 mg daily at bedtime for up to 8 wk Pathologic hypersecretory conditions • Adult: PO 20 mg q6hr; may give up to 160 mg q6hr if needed; IV 20 mg q6hr if unable to take PO GERD • Adult/child ≥ 40 kg: PO 20 mg bid for up to 6 wks; 20-40 mg bid up to 12 wk (ulcerative esophagitis) • Child 1-16 yr: PO 0.5 mg/kg bid, max 40 mg bid • Child 3 mo-<1 yr: PO 0.5 mg/kg/dose bid ≤8 wk • Child <3 mo: PO 0.5 mg/kg/dose daily ≤8 wk Heartburn relief/prevention (OTC) • Adult/child >12 yr: PO 10 mg with water for relief or take 15 min-1 hr be- fore eating for prevention Renal dose F • Adult: PO CCr <50 mL/min give 1⁄2 dose or increase interval to q36-48h
Source pages 543, 544, 545
Available forms: Tabs 125, 250, 500 mg Available forms: Tabs 10, 20, 40 mg; powder for oral susp 40 mg/5 mL; inj 0.4 mg/mL premixed in normal saline, 10 mg/mL, 20 mg/50 mL; tabs chewable 10, 20 mg
Source pages 544, 545
Administer: • Without regard to meals • As soon as diagnosed; for herpes zoster within 72 hr Administer: • Store in cool environment (oral); IV sol stable for 48 hr at room temperature; do not use discolored sol; discard un- used oral sol after 1 mo PO route • After shaking oral suspension • Give without regard to meals • Store suspension room temperature, discard after 30 days • Protect tablets from light Direct IV route • After diluting 2 mL of product (10 mg/ mL) in 0.9% NaCl to total volume of 5-10 mL; inject over 2 min to prevent hypotension Intermittent IV INFUSION route • After diluting 20 mg (2 mL) of product in 100 mL of LR, 0.9% NaCl, D5W, D10W; run over 15-30 min, stable for 48 hr after dilution refrigerated Y-site compatibilities: Acyclovir, alfent- anil, allopurinol, amifostine, amikacin, ami- nocaproic acid, aminophylline, amioda- rone, amphotericin B lipid complex, amphotericin B liposome, amsacrine, anakinra, anidulafungin, ascorbic acid injection, atenolol, atracurium, atropine, aztreonam, benztropine, bivalirudin, bleo- mycin, bumetanide, buprenorphine, butor- phanol, calcium chloride/gluconate, CAR- BOplatin, caspofungin, cefonicid, cefotaxime, cefTAZidime, cefuroxime, chlor- proMAZINE, cimetidine, cisatracurium, CIS- platin, cladribine, clindamycin, codeine, cyanocobalamin, cyclophosphamide, cyclo- SPORINE, cytarabine, DACTINomycin, DAP- TOmycin, dexamethasone, dexmedetomi- dine, digoxin, diltiazem, diphenhydrAMINE, DOBUTamine, DOCEtaxel, DOPamine, doripenem, doxacurium, DOXOrubicin, DOXOrubicin liposomal, doxycycline, dro- peridol, enalaprilat, ePHEDrine, EPINEPH- rine, epirubicin, epoetin alfa, eptifibatide, ertapenem, erythromycin, esmolol, etopo- side, fenoldopam, fentaNYL, filgrastim, flu- conazole, fludarabine, fluorouracil, folic acid, gatifloxacin, gemcitabine, gentamicin, glycopyrrolate, granisetron, heparin, hydro- cortisone, HYDROmorphone, hydrOXYzine, IDArubicin, ifosfamide, imipenem-cilastatin, irinotecan, isoproterenol, ketorolac, labet- alol, levofloxacin, lidocaine, linezolid, LORazepam, LR, magnesium sulfate, man- nitol, mechlorethamine, melphalan, meper- idine, metaraminol, methicillin, methotrex- ate, methoxamine, methyldopate, methylPREDNISolone, metoclopramide, metoprolol, metroNIDAZOLE, miconazole, midazolam, milrinone, mitoXANtrone, mor- phine, moxalactam, multiple vitamins injec- tion, mycophenolate, nafcillin, nalbuphine, naloxone, nesiritide, netilmicin, niCARdi pine, nitroglycerin, nitroprusside, norepi- nephrine, 0.9% NaCl, octreotide, ondanse- tron, oxacillin, oxaliplatin, oxytocin, PACLitaxel, palonosetron, pamidronate, pancuronium, papaverine, PEMEtrexed, penicillin G potassium/sodium, pentami- dine, pentazocine, PENTobarbital, perphen- azine, PHENobarbital, phenylephrine, phyto- nadione, polymyxin B, potassium chloride/ phosphates, procainamide, prochlorpera- zine, promethazine, propofol, propranolol, protamine, pyridoxine, quiNIDine, raniti- dine, remifentanil, Ringer’s, ritodrine, riTUXimab, sargramostim, sodium acetate/ bicarbonate, succinylcholine, SUFentanil, tacrolimus, teniposide, theophylline, thia- mine, thiotepa, ticarcillin, ticarcillin-clavula- nate, tigecycline, tirofiban, TNA, tobramycin, tolazoline, TPN, trastuzumab, trimetaphan, urokinase, vancomycin, vasopressin, vecuronium, verapamil, vinCRIStine, vinorelbine, voriconazole, zoledronic acid
Source pages 544, 545, 546
Extracted information for famciclovir only.
Assess: • Herpes zoster: severity of the break- out; burning, itching, pain, which are early symptoms of herpes infection; as- sess daily during therapy • Monitor CBC, LFTs test if on long-term treatment • Acute renal failure: usually in high dose or in those >65 yr; urine CCr; BUN before and during treatment if decreased renal function; dose may have to be low- ered; hepatic studies: LFTs • Bowel pattern before, during treat- ment; diarrhea may occur • Postherpetic neuralgia during and after treatment • Pregnancy/breastfeeding: use only if benefits outweigh fetal risk; pregnant patients should enroll in the Famvir pregnancy reporting system, 1-888- 669-6682; excretion unknown in breast milk Assess: • Ulcers: epigastric pain, adominal pain, frank or occult blood in emesis, stools • Renal function: patients with decreased renal function are at risk for pro- longed QT • Intragastric pH, serum creatinine/BUN baseline and periodically • For bleeding, hematuria, hematuresis, occult blood in stools; abdominal pain • Increase in bulk and fluids in diet to prevent constipation • Beers: avoid in older adults with de- lirium or at high risk for delirium; may induce or worsen the condition; assess for confusion • Pregnancy/breastfeeding: cautious use in pregnancy, breastfeeding; excreted in breast milk
Source pages 544, 546, 547
Evaluate: • Therapeutic response: decreased size, spread of lesions Evaluate: • Therapeutic response: decreased ab- dominal pain, healing of duodenal ul- cers, decreased gastroesophageal reflux
Source pages 544, 547
CLINICAL CONSIDERATIONS CLINICAL CONSIDERATIONS
Source pages 544, 546
Patient and caregiver information: • How to recognize beginning infection (pain, itching, tingling), use product within 48 hr of rash/urticaria • How to prevent spread of infection; that this medication does not prevent spread to others; that condoms should be used; that until crusting of lesions has taken place, not to be around those who have not had the chicken pox vac- cine or those who are immunocompro- mised • About the reason for medication, ex- pected results; that product must be taken for whole course of treatment; if lactose intolerant, to notify prescriber before use • That women with genital herpes should have yearly Pap smears; that cervical cancer is more likely • To avoid driving or other hazardous activities until results are known; dizzi- ness may occur (fa-moe′ti-deen) Pepcid, Pepcid AC, Zantac Patient and caregiver information: • That product must be continued for prescribed time in prescribed method to be effective; not to double dose; do not take for extended periods of time, risk of B12 malabsorption • About possibility of decreased libido; that this is reversible after discontinuing therapy • To avoid irritating foods, alcohol, aspi- rin, NSAIDs, extreme-temperature foods that may irritate GI system • That smoking should be avoided because it diminishes effectiveness of product • To avoid tasks requiring alertness be- cause dizziness, drowsiness may occur
Source pages 544, 545, 547
Extracted information for famciclovir only.
PHARMACOKINETICS Bioavailability 77%, 20% protein bind- ing, 73% excreted via kidneys, half-life 2-3 hr, peak 1 hr, duration 12 hr PHARMACOKINETICS Protein binding 15%-20%, metabolized in liver 30% (active metabolites), 70% excreted by kidneys, half-life 21⁄2-31⁄2 hr PO: Onset 60 min, duration 12 hr, peak 1-3 hr, absorption 50% IV: Onset 60 min, peak 1-4 hr, duration 8-12 hr
Source pages 544, 546
Filter the extracted dose blocks for this individual drug.
Acute herpes zoster (Shingles)
• Adult: PO 500 mg q8hr for 7 days Renal dose
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr 40-59 mL/min, 500 mg q12hr; CCr 20-39 mL/min, 500 mg q24hr; CCr <20 mL/min, 250 mg q24hr Suppression of recurrent herpes simplex
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 250 mg q12hr up to 1 yr Renal dose
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr 20-39 mL/min, 125 mg q12hr × 5 days; CCr <20 mL/min, 125 mg q24hr × 5 days Recurrent herpes labialis (cold sores)
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 1500 mg single dose Renal impairment: recurrent herpes labialis
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr ≥60 mL/min, usual dose; CCr 40-59 mL/min, 750 mg as a single dose; CCr 20-39 mL/min, 500 mg as single dose; CCr <20 mL/min, 250 mg as a single dose; hemodialysis, 250 mg as a single dose following dialysis Recurrent mucocutaneous orolabial genital herpes simplex infections in HIV
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 500 mg bid × 7 days Renal impairment: recurrent orolabial or genital herpes in HIV-infected patients
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr ≥40 mL/min, usual dose; CCr 20-39 mL/min, 500 mg q24hr; CCr <20 mL/min, 250 mg q24hr; hemodialysis, 250 mg following each dialysis Recurrent genital herpes simplex
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 1000 mg bid on a single day Renal dose
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr 40-59 mL/min, 500 mg q12hr × 1 day; CCr 20-39 mL/min, 500 mg as a single dose; CCr <20 mL/min, 250 mg as a single dose Chickenpox (unlabeled)
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 500 mg q8hr × 7 days, preferably within 48 hr of onset DOSAGE AND ROUTES Short-term treatment of benign gastric ulcer
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult/child ≥ 40 kg: PO 40 mg/day at bedtime × 4-8 wk, then 20 mg/day at bedtime if needed (maintenance); IV 20 mg q12hr if unable to take PO
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult/child ≥ 40 kg: PO 40 mg at bedtime or 20 mg bid; maintenance 20 mg daily at bedtime for up to 8 wk Pathologic hypersecretory conditions
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO 20 mg q6hr; may give up to 160 mg q6hr if needed; IV 20 mg q6hr if unable to take PO GERD
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult/child ≥ 40 kg: PO 20 mg bid for up to 6 wks; 20-40 mg bid up to 12 wk (ulcerative esophagitis)
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult/child >12 yr: PO 10 mg with water for relief or take 15 min-1 hr be- fore eating for prevention Renal dose F
Candidate age grouping · source pages 543, 544, 545
Acute herpes zoster (Shingles)
• Adult: PO CCr <50 mL/min give 1⁄2 dose or increase interval to q36-48h
Candidate age grouping · source pages 543, 544, 545