What does foscarnet mean?
Foscarnet is an antiviral medication used mainly in hospital settings to combat serious infections caused by members of the herpesvirus family. Its most important role is in treating cytomegalovirus (CMV) disease — particularly CMV retinitis, which can threaten sight in people with weakened immune systems — and it is also a key option against herpes simplex and varicella-zoster viruses that have become resistant to acyclovir. Unlike many antivirals, foscarnet does not require activation by viral enzymes; instead, it acts directly on viral DNA polymerase and reverse transcriptase, blocking the replication of viral genetic material. The drug is given intravenously and demands careful monitoring, since it can cause kidney damage and electrolyte imbalances. Chemically, it is trisodium phosphonoformate, a name reflected in the word itself. Though rarely heard outside clinical practice, foscarnet occupies a crucial niche in medicine as a second-line therapy when standard antiviral treatments fail, making it a significant term in infectious-disease care.
nounFoscarnet is an antiviral medication used primarily to treat cytomegalovirus (CMV) infections such as CMV retinitis, and infections caused by herpesviruses resistant to acyclovir. It works by directly inhibiting viral DNA polymerase and reverse transcriptase.
- An antiviral drug (trisodium phosphonoformate) used to treat CMV infections and acyclovir-resistant herpesvirus infections by inhibiting viral DNA polymerase.
"The patient's acyclovir-resistant herpes infection was treated with intravenous foscarnet."
"Because the transplant recipient developed CMV retinitis, the physicians began a course of intravenous foscarnet."
"Foscarnet remains a valuable option when herpes simplex viruses have become resistant to acyclovir."
Plural use is rare and appears only in pharmacological writing referring to different formulations or salts of the substance; in practice foscarnet is almost always treated as a mass noun.
"Different foscarnet formulations were compared in the pharmacology review."
Its very name is a contraction of its chemical identity — 'fos' from phosphonoformic acid — making foscarnet one of the few drugs whose brand-style name literally encodes its own chemistry.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of foscarnet
The name foscarnet derives from its chemical identity as a phosphonoformate compound, contracted from 'phosphonoformate' (the 'fos' reflecting the phospho- element). Developed as an antiviral agent in research during the late twentieth century, it was adopted into clinical medicine for treating CMV and drug-resistant herpesvirus infections. As a modern proprietary-sounding drug name rather than a classical loanword, it has no true cognates in earlier languages beyond other terms built on the phosphorus-related chemical roots of its parent compound.
How foscarnet is actually used
Foscarnet is a technical, medical-register term encountered almost exclusively in clinical, pharmacological, and scientific contexts. It is administered intravenously and is associated with significant renal toxicity, so it typically appears in discussions of hospital treatment rather than everyday conversation.
Easily confused with foscarnet
Foscarnet is an injectable antiviral drug, whereas famotidine is an oral medication that reduces stomach acid to treat heartburn and ulcers.