haʊˈɛvɚ, ʌnlˈaɪk ɐkˈaɪkləvˌɪɹ ænd ɡˈænsɪklˌʌvɪɹ, fˈɑːskɑːɹnɪt ɪz nˌɑːt ˈæktᵻvˌeɪɾᵻd baɪ vˈaɪɚɹəl pɹˈoʊtiːn kˈɪneɪsᵻz, mˌeɪkɪŋ ɪt jˈuːsfəl ɪn ɐkˈaɪkləvˌɪɹ ɔːɹ ɡˈænsɪklˌʌvɪɹᵻsˈɪstənt ˌeɪtʃˌɛsvˈiː ænd sˌiːˌɛmvˈiː ɪnfˈɛkʃənz.
However, unlike acyclovir and ganciclovir, foscarnet is not activated by viral protein kinases, making it useful in acyclovir- or ganciclovir-resistant HSV and CMV infections.