amenorrhea or ovarian failure, cyclophosphamide is used for early phases of treatment and later substituted by other medications, such as mycophenolic acid or ACA. AL amyloidosis Cyclophosphamide, used in combination with thalidomide or lenalidomide and dexamethasone has documented efficacy as an off-label treatment of AL amyloidosis. It appears to be an alternative to the more traditional treatment with melphalan in people who are ill-suited for autologous stem cell transplant. Graft-versus-host disease Graft-versus-host disease (GVHD) is a major barrier for allogeneic stem cell transplant because of the immune reactions of donor T cell against the person receiving them. GVHD can often be avoided by T-cell depletion of the graft. The use of a high dose cyclophosphamide post-transplant in a half matched or haploidentical donor hematopoietic stem cell transplantation reduces GVHD, even after using a reduced conditioning regimen. Contraindications Like other alkylating agents, cyclophosphamide is teratogenic and contraindicated in pregnant women (pregnancy category D) except for life-threatening circumstances in the mother. Additional relative contraindications to the use of cyclophosphamide include lactation, active infection, neutropenia or bladder toxicity. Cyclophosphamide is a pregnancy category D drug and causes birth defects. First trimester exposure to cyclophosphamide for the treatment of cancer or lupus displays a pattern of anomalies labeled "cyclophosphamide embryopathy", including growth restriction, ear and facial abnormalities, absence of digits and hypoplastic limbs. Side effects Adverse drug reactions from cyclophosphamide are related to the cumulative medication dose and include chemotherapy-induced nausea and vomiting, bone marrow suppression, stomach ache, hemorrhagic cystitis, diarrhea, darkening of the skin/nails, alopecia (hair loss) or thinning of hair, changes in color and texture of the hair, lethargy, and profound gonadotoxicity. Other side effects may include easy bruising/bleeding, joint pain, mouth sores, slow-healing existing wounds, unusual decrease in the amount of urine or unusual tiredness or weakness. Potential side effects also include leukopenia, infection, bladder toxicity, and cancer. Pulmonary injury appears rare, but can present with two clinical patterns: an early, acute pneumonitis and a chronic, progressive fibrosis. Cardiotoxicity is a major problem with people treated with higher dose regimens. High-dose intravenous cyclophosphamide can cause the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and a potentially fatal hyponatremia when compounded by intravenous fluids administered to prevent drug-induced cystitis. While SIADH has been described primarily with higher doses of cyclophosphamide, it can also occur with the lower doses used in the management of inflammatory disorders. Bladder bleeding Acrolein is toxic to the