Foscavir


Also found in: Dictionary, Wikipedia.

foscarnet

(foss-kar-net) ,

Foscavir

(trade name)

Classification

Therapeutic: antivirals
Pregnancy Category: C

Indications

Treatment of cytomegalovirus (CMV) retinitis in HIV-infected patients (alone or with ganciclovir).Treatment of acyclovir-resistant mucocutaneous herpes simplex virus (HSV) infections in immunocompromised patients.

Action

Prevents viral replication by inhibiting viral DNA-polymerase and reverse transcriptase.

Therapeutic effects

Virustatic action against susceptible viruses including CMV.

Pharmacokinetics

Absorption: IV administration results in complete bioavailability.
Distribution: Variable penetration into CSF. May concentrate in and be slowly released from bone.
Metabolism and Excretion: 80–90% excreted unchanged in urine.
Half-life: 3 hr (in patients with normal renal function); longer half-life of 90 hr may reflect release of drug from bone.

Time/action profile

ROUTEONSETPEAKDURATION
IVrapidend of infusion8–24 hr

Contraindications/Precautions

Contraindicated in: Hypersensitivity.
Use Cautiously in: Renal impairment (dose ↓ required if CCr ≤1.4–1.6 mL/min/kg; see product information);History of seizures; Obstetric / Lactation / Pediatric: Safety not established.

Adverse Reactions/Side Effects

Central nervous system

  • seizures (life-threatening)
  • headache (most frequent)
  • anxiety
  • confusion
  • dizziness
  • fatigue
  • malaise
  • mental depression
  • weakness

Ear, Eye, Nose, Throat

  • conjunctivitis
  • eye pain
  • vision abnormalities

Respiratory

  • coughing
  • dyspnea

Cardiovascular

  • chest pain
  • ECG abnormalities
  • edema
  • palpitations

Gastrointestinal

  • diarrhea (most frequent)
  • nausea (most frequent)
  • vomiting (most frequent)
  • abdominal pain
  • abnormal taste sensation
  • anorexia
  • constipation
  • dyspepsia

Genitourinary

  • renal failure (most frequent)
  • albuminuria
  • dysuria
  • nocturia
  • polyuria
  • urinary retention

Dermatologic

  • ↑ sweating
  • pruritus
  • rash
  • skin ulceration

Fluid and Electrolyte

  • hypocalcemia (most frequent)
  • hypokalemia (most frequent)
  • hypomagnesemia (most frequent)
  • hyperphosphatemia
  • hypophosphatemia

Hematologic

  • anemia (most frequent)
  • granulocytopenia
  • leukopenia

Local

  • pain/inflammation at injection site

Musculoskeletal

  • arthralgia (most frequent)
  • myalgia (most frequent)
  • back pain
  • involuntary muscle contraction

Neurologic

  • ataxia
  • hypoesthesia
  • neuropathy
  • paresthesia
  • tremor

Miscellaneous

  • fever (most frequent)
  • chills
  • flu-like syndrome
  • lymphoma
  • sarcoma

Interactions

Drug-Drug interaction

Concurrent use with parenteral pentamidine may result in severe, life-threatening hypocalcemia.Risk of nephrotoxicity may be ↑ by concurrent use of other nephrotoxic agents (amphotericin B, aminoglycosides ).

Route/Dosage

Intravenous (Adults) CMV retinitis—60 mg/kg q 8 hr or 90 mg/kg q 12 hr for 2–3 wk, then 90–120 mg/kg/day as a single dose. Dose ↓ required for any degree of renal impairment; HSV—40 mg/kg q 8–12 hr for 2–3 wk or until healing occurs.

Availability (generic available)

Solution for injection: 24 mg/mL

Nursing implications

Nursing assessment

  • CMV Retinitis: Diagnosis of CMV retinitis should be determined by ophthalmoscopy before treatment with foscarnet. Ophthalmologic examinations should also be performed at the conclusion of induction and every 4 wk during maintenance therapy.
  • Culture for CMV (urine, blood, throat) may be taken before administration. However, a negative CMV culture does not rule out CMV retinitis.
  • HSV Infections: Assess lesions before and daily during therapy.
  • Lab Test Considerations: Monitor serum creatinine before and 2–3 times weekly during induction therapy and at least once every 1–2 wk during maintenance therapy. Monitor 24-hr CCr before and periodically throughout therapy. If CCr drops below 0.4 mL/min/kg, discontinue foscarnet.
    • Monitor serum calcium, magnesium, potassium, and phosphorus before and 2–3 times weekly during induction therapy and at least weekly during maintenance therapy. May cause ↓ concentrations.
    • May cause anemia, granulocytopenia, leukopenia, and thrombocytopenia. May cause ↑ AST and ALT levels and abnormal A-G ratios.

Potential Nursing Diagnoses

Risk for infection (Indications)

Implementation

  • Adequately hydrate patient with 750–1000 mL of 0.9% NaCl or D5W before first infusion to establish diuresis, then administer 750–1000 mL with 120 mg/kg of foscarnet or 500 mL with 40–60 mg/kg of foscarnet with each dose to prevent renal toxicity.
  • Intravenous Administration
  • pH: 7.4.
  • Intermittent Infusion: Diluent: May be administered via central line undiluted. If administered via peripheral line, must be diluted with D5W or 0.9% NaCl to prevent vein irritation. Do not administer solution that is discolored or contains particulate matter. Use diluted solution within 24 hr.Concentration: Undiluted: 24 mg/mL; Diluted: 12 mg/mL.
    • Dose is based on patient weight; excess solution may be discarded from bottle before administration to prevent overdosage.
    • Patients who experience progression of CMV retinitis during maintenance therapy may be retreated with induction therapy followed by maintenance therapy.
  • Rate: Administer at a rate not to exceed 1 mg/kg/min.
    • Infuse solution via infusion pump to ensure accurate infusion rate.
  • Y-Site Compatibility: aldesleukin, amikacin, aminophylline, ampicillin, anidulafungin, aztreonam, bivalirudin, bleomycin, carboplatin, carmustine, cefazolin, cefoperazone, cefoxitin, ceftazidime, ceftriaxone, cefuroxime, chloramphenicol, cisplatin, clindamycin, cyclophosphamide, cytarabine, dactinomycin, daptomycin, dexamethasone sodium phosphate, dexmedetomidine, diltiazem, docetaxel, dopamine, doripenem, doxacurium, ertapenem, erythromycin lactobionate, etoposide, etoposide phosphate, fenoldopam, fluconazole, flucytosine, fludarabine, fluorouracil, furosemide, gemcitabine, gentamicin, granisetron, heparin, hydrocortisone, hydromorphone, ifosfamide, imipenen-cilastatin, irinotecan, linezolid, mechlorethamine, methotrexate, metoclopramide, metronidazole, morphine, nafcillin, nesiritide, octreotide, oxacillin, oxaliplatin, oxytocin, paclitaxel, palonosetron, pamidronate, pantoprazole, pemetrexed, penicillin G potassium, phenytoin, piperacillin/tazobactam, potassium acetate, ranitidine, tacrolimus, teniposide, thiotepa, ticarcillin/clavulanate, tigecycline, tirofiban, tobramycin, vincristine, voriconazole, zoledronic acid
  • Y-Site Incompatibility: Manufacturer recommends that foscarnet not be administered concurrently with other drugs or solutions in the same IV catheter except D5W or 0.9% NaClacyclovir, amphotericin B colloidal, amphotericin B lipid complex, caspofungin, diazepam, digoxin, diphenhydramine, dobutamine, doxorubicin, droperidol, epirubicin, ganciclovir, haloperidol, idarubicin, leucovorin, midazolam, mitoxantrone, mycophenolate, pentamidine, prochlorperazine, promethazine, vinorelbine

Patient/Family Teaching

  • Inform patient that foscarnet is not a cure for CMV retinitis. Progression of retinitis may continue in immunocompromised patients during and after therapy. Advise patients to have regular ophthalmologic exams.
  • Advise patient to notify health care professional immediately if perioral tingling or numbness in the extremities or paresthesia occurs during or after infusion. If these signs of electrolyte imbalance occur during administration, infusion should be stopped and lab samples for serum electrolyte concentrations obtained immediately.
  • Emphasize the importance of frequent follow-up exams to monitor renal function and electrolytes.

Evaluation/Desired Outcomes

  • Management of the symptoms of CMV retinitis in patients with AIDS.
  • Crusting over and healing of skin lesions in HSV infections.

Foscavir

(fŏs′kə-vîr′)
A trademark for the drug foscarnet sodium.

Foscavir

a trademark for an antiviral drug (foscarnet) used in the treatment of cytomegalovirus retinitis in conjunction with ganciclovir and for the treatment of herpes simplex infections when acyclovir fails.

Foscavir

A brand name for FOSCARNET.
References in periodicals archive ?
We also believe that the acquisition improves Clinigen's quality of earnings, as the proportion of gross profit derived from its Foscavir drug is much reduced.
In October the company received a top US award for making a pioneering new drug - Foscavir - more widely available.
The deal comes after Clinigen gaining the anti-viral Foscavir from AstraZeneca in 2010.
Currently, only two drugs, Cytovene and Foscavir, are commonly used for treatment of HHV-6.
Immunosuppressive therapy was stopped, and Foscavir (6 g/d) and intravenous immunoglobulins (total dose 2 g/ kg) were added to the broad spectrum antimicrobial drugs given since admission.
Approved February 1997 for combination therapy with foscavir and ganciclovir of patients who have relapsed after monotherapy with either drug.
Hospira granted exclusive rights to market, promote and distribute Foscavir in the US
50] Virus Foscavir 50-800 [micro]mol/L Cytomegalovirus 5-443 [micro]mol/L Herpes simplex mutants Acyclovir 0.
Clinigen Healthcare acquired Foscavir (foscarnet sodium) from AstraZeneca in 2010, seeing sales grow six-fold in 2011.
In March 2010, Clinigen acquired from AstraZeneca exclusive rights to the antiviral Foscavir in all global markets.
Last year, the program added several medications for people with HIV/AIDS, including Videx, Hivid, Zovirax, Foscavir and Cipro.
In addition to Xylocaine (lidocaine) and Sensorcaine (bupivacaine HCl), the company's key products in the United States include Streptase (streptokinase) and two products introduced within the last two years, Foscavir (foscarnet sodium) Injection and Toprol-XL (metoprolol succinate).