אבן העזר ע״טEven HaEzer 79

Se’if 1א׳

רְפוּאָתָהּ כֵּיצַד, לָקְתָה, חַיָּב לְרַפּאוֹתָהּ, בֵּין רְפוּאָה שֶׁיֵּשׁ לָהּ קִצְבָה בֵּין רְפוּאָה שֶׁאֵין לָהּ קִצְבָה; אֲבָל אַלְמְנָתוֹ אֵינָהּ מִתְרַפֵּאת מִנְּכָסָיו, אֶלָּא בִּרְפוּאָה שֶׁאֵין לָהּ קִצְבָה, שֶׁהִיא דּוֹמָה לִמְזוֹנוֹת:

How is he required to pay for her healing? If she became ill, he must heal her (pay her medical costs), whether healing that has a determinate cost or an indeterminate cost. But his widow is not healed from his estate except for healing which has no determinate cost, which is similar to food [payments].

Se’if 2ב׳

רָצוּ הַיּוֹרְשִׁין לִקְצֹב עִם הָרוֹפֵא, כְּדֵי שֶׁיִּהְיֶה לָהּ קִצְבָה וְיִפָּטְרוּ מִמֶּנָּה, הָרְשׁוּת בְּיָדָם:

If the heirs wish to specify a cost with the doctor, such that [her healing] will have a determinate cost and they will be relieved of payment, they are permitted to do so.

Se’if 3ג׳

אִם רָאָה הַבַּעַל שֶׁהַחֹלִי אָרֹךְ, יָכוֹל לוֹמַר לָהּ: הֲרֵי כְּתֻבָּתֵךְ מֻנַּחַת, אוֹ רַפְּאִי עַצְמֵךְ מִכְּתֻבָּתֵךְ אוֹ הֲרֵינִי מְגָרְשֵׁךְ וְנוֹתֵן כְּתֻבָּה; וְאֵין רָאוּי לַעֲשׂוֹת כֵּן מִפְּנֵי דֶּרֶךְ אֶרֶץ:

If a woman contracts a lasting disease, he is able to say to her that the ketuba can be assumed if she heals herself or the ketuba can be absolved and give her the ketuba , but this is not proper behavior because it is not derech eretz .