Unfortunately, the real cause of scleroderma (systemic sclerosis) has not been found out yet. Hence, the treatment is mainly symptomatic i.e. dealing with symptoms for as long as it is necessary. Hence, it is not possible to put a time frame. Trental (pentoxiphylline) is actually indicated in peripheral vascular diseases to increase blood supply. Azoran (azathioprine) is immunosuppressant and is normally meant for prevention of rejection of transplanted organs (such as kidneys) but is also given in other disorders where there is possibility of immunological problem. Like most other medicines, both do have side effects but one has to weigh the benefits against side effects.