Figure 1.

Study design

1. The number of days in the screening phase was determined by washout time of patient's previous medications.
2. Patients who could not tolerate the 150 mg dose had to exit the study.
3. Patients who could not tolerate the next dose after trying it for at least 2 days could decrease to the previous dose. In rare cases, if the patient was unable to tolerate the higher dose after trying it for at least 1 day, the dose could be decreased to the previous level. Patients were allowed to decrease their dose only once during the titration period.
4. Patients had to stay at the final titration dose until the end of titration.