Chlorambucil is an alkilating agent that is used for the treatment of immune mediated diseases. It causes DNA breaks and cross-links. Bone marrow suppression is the most common side effect but overall chlorambucil is considered safer than azathioprine especially for cats. Gold is used for the therapy of immune mediated diseases. It suppresses antibody synthesis and cell mediated immunity.
Parental gold is more effective than the oral form.
Initially, lower doses are given to test possible hypersensitivity of the patient. There is a lag phase of 6-12 weeks until the full effect is seen. Cyclophosphamide is an alkilating agent that inhibits rapidly growing population of cells. Prevention of mitosis occurs because of interference with DNA replication and RNA translation. Side effects include severe bone marrow suppression, hemorrhagic cystitis, bladder fibrosis, teratogenesis and infertility.