Rewrite this sentence using the same information but using the past perfect tense
The patient had taken the antibiotic for two days.
The patient had been taking the antibiotic for two days.
Complete the following task based on the instruction and optional input provided.### Instruction:
Rewrite this sentence using the same information but using the past perfect tense

### Input:
The patient had taken the antibiotic for two days.

### Output:
The patient had been taking the antibiotic for two days.