No hemolytic anemia is not a permanent condition. It is caused by a lack of ability of the RBC (red blood cell) to metabolise the drug. It (ribavirin) accumulates in the RBC and eventually lysis (breaks open) the cell destroying it. The typical life-span of a RBC is about 120 days and typically RBC #'s and hemoglobin numbers return to normal levels within (and usually sooner) this time frame once the drug is stopped.
The spanish post below appears to me that ribavirin is only used for a short period of time to shorten the time span of an outbreak. It does not appear to offer a cure based on that single post. Does anyone have any other references to ribavirin and the treatment of herpes?