Learn Hardcore Chinese: wǒ xīwàng chī le yào yǐhòu, míngtiān zǎoshang jiù néng tuìshāo. - I hope that after taking the medicine, my fever will go down by tomorrow morning.

Breakdown of wǒ xīwàng chī le yào yǐhòu, míngtiān zǎoshang jiù néng tuìshāo.

Used after a verb. Marks that an action is completed.

Why does Chinese use 吃药 for take medicine? Doesn’t 吃 literally mean eat?

Yes, 吃 literally means eat, but in Chinese 吃药 is the normal everyday way to say take medicine.

A few useful comparisons:

So although the literal wording may sound strange in English, 吃药 is completely natural in Mandarin.

What does the 了 in 吃了药 mean here?

Here, 了 marks the action as completed: after having taken the medicine.

So:

吃药以后 = after taking medicine / after taking medicine in general
吃了药以后 = after having taken the medicine, with clearer emphasis that the action is completed first

This 了 is not simply a past-tense marker like English -ed. It is an aspect marker, showing completion of the action.

Why is 以后 used after 吃了药?

以后 means after.

In Chinese, a very common pattern is:

verb phrase + 以后 = after doing ...

So:

This whole part acts like a time-setting phrase for the rest of the sentence.