2.4. Randomization and treatment
Eligible participants who have VAS scores ≥ 30 at screening will be randomized to receive either IR or SR pregabalin in a 1:1 ratio by a computer-generated sequence without stratification. Pregabalin will be administered open-label, and patients will receive the assigned medication for 8 weeks. The study group will receive SR pregabalin tablets of 150 mg once a day starting in the evening, and the control group will receive IR pregabalin capsules of 75 mg twice a day until the morning of the last day of the study (Fig. Study design.The investigator or clinical research coordinator will provide participants with instructions on how to take medication correctly. We will assess medication adherence by determining the amount of study drug not administered at the end of study visit (visit 3). At the final visit, all study drug (leftover tablets and packs) will be collected, and the investigator will check the quantity of the study drug. The number of days between the last visit and end of the treatment period will also be recorded. The percentage of medication adherence will be calculated by dividing the number of pills taken by the number of pills scheduled for administration during the treatment period. If a subject loses their study drug, they must receive a medical examination to confirm the loss, which will then be recorded in the source document and case report form.