foscarnet trisodium hexahydrate at a glance
Medicine class
Direct-acting antiviral and phosphonic acid derivative
Administration
Given only into a vein by a healthcare professional
Key safety issue
Kidney function and blood mineral levels require close monitoring
Hydration
Adequate fluid intake or intravenous hydration helps reduce kidney toxicity
What is foscarnet trisodium hexahydrate used for?
Licensed uses for the selected product are:
Cytomegalovirus retinitis in patients with AIDS.
Mucocutaneous herpes simplex virus infection that is clinically unresponsive to aciclovir in immunocompromised patients.
It is not licensed for other CMV infections, other forms of HSV infection or use in immunocompetent people.
How does foscarnet trisodium hexahydrate work?
Foscarnet directly blocks viral DNA polymerase and reverse transcriptase, enzymes susceptible viruses need to copy their genetic material. It does not need activation by viral thymidine kinase, which helps explain its activity against some aciclovir-resistant herpes simplex viruses.
foscarnet trisodium hexahydrate preparations and strengths
Solution for infusion
Route: Intravenous
Strengths: 24 mg/mL
How to take foscarnet trisodium hexahydrate
This treatment is administered in hospital or another specialist setting as an intravenous infusion. The clinical team selects central or peripheral venous access and arranges any necessary pharmacy dilution.
Do not interfere with the infusion or venous line.
Maintain hydration as directed by the clinical team.
Tell staff promptly about tingling, nausea, pain, redness or swelling during the infusion.
Clean the genital area carefully after passing urine to reduce irritation from medicine excreted in urine.
Rinse immediately with water if the solution contacts skin or eyes.
foscarnet trisodium hexahydrate side effects
Common or expected effects
- Nausea, vomiting, diarrhoea or reduced appetite
- Headache, dizziness or tingling
- Weakness, tiredness, fever or chills
- Rash
- Changes in kidney function
- Low calcium, magnesium or potassium
- Anaemia or reduced white blood cells
- Infusion-site pain or inflammation
- Genital discomfort or ulceration
Get urgent medical advice
- Severe allergic reaction, including facial or throat swelling, breathing difficulty, collapse or shock
- Blistering, peeling or widespread severe skin reaction
- Seizure or severe confusion
- Abnormal heart rhythm, fainting or persistent palpitations
- Acute kidney injury, including markedly reduced urine
- Severe electrolyte disturbance causing spasms, weakness or pronounced tingling
- Severe abdominal pain that may indicate pancreatitis
- Unusual bleeding or signs of serious infection
foscarnet trisodium hexahydrate in pregnancy
Human pregnancy information is limited, and the selected product is not recommended during pregnancy. People who are pregnant, planning pregnancy or able to conceive should discuss treatment and effective contraception with the specialist team. Men should avoid fathering a child during treatment and for six months afterwards.
foscarnet trisodium hexahydrate while breastfeeding
Foscarnet should not be used while breastfeeding because transfer into human milk is uncertain and risk to the infant cannot be excluded. The specialist team must consider whether breastfeeding or treatment should be stopped.
foscarnet trisodium hexahydrate interactions
The clinical team should review all prescribed, non-prescription and intravenous medicines before treatment.
Aminoglycosides, amphotericin B, ciclosporin, aciclovir, methotrexate or tacrolimus
Combining nephrotoxic medicines can increase kidney injury risk and requires closer monitoring.
Intravenous pentamidine
The combination has caused kidney impairment and symptomatic low calcium and should be approached with extreme caution.
QT-prolonging medicines, including quinidine, amiodarone, sotalol and some neuroleptics
Concurrent use may increase the risk of serious ventricular arrhythmias and can require cardiac monitoring.
Common questions about foscarnet trisodium hexahydrate
Answers are fully visible for fast scanning and source review.
Why is foscarnet used when aciclovir has not worked?
It does not require activation by viral thymidine kinase, so it may remain active against some herpes simplex viruses that are resistant or clinically unresponsive to aciclovir.
Why are kidney tests needed?
Foscarnet is cleared mainly through the kidneys and can impair renal function, so treatment must be reassessed when kidney function changes.
Why is hydration important?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.