| The most common adverse reactions include ulcerative stomatitis, leukopenia, nausea and abdominal distress. Although very rare, anaphylactic reactions to methotrexate have occurred.Others reported are malaise, undue fatigue, chills and fever, dizziness and decreased resistance to infection. Opportunistic infections (sometimes fatal e.g. fatal sepsis) have also been reported in patients receiving methotrexate therapy for neoplastic and non-neoplastic diseases, Pneumocystis carinii pneumonia being the most common. Other reported infections include, pneumonia, nocardiosis, histoplasmosis, cryptococcosis, Herpes Zoster, Herpes Simplex, hepatitis and disseminated Herpes Simplex and cytomegalovirus infection, including cytomegaloviral pneumonia. In general, the incidence and severity of side effects are considered to be doserelated.Adverse reactions as reported for the various systems are as follows:Skin: Stevens-Johnson syndrome, epidermal necrolysis, erythematous rashes, pruritus, urticaria, photosensitivity, pigmentary changes, alopecia, ecchymosis, telangiectasia, acne, furunculosis.Lesions of psoriasis may be aggravated by concomitant exposure to ultraviolet radiation. Skin ulceration in psoriatic patients and rarely painful erosion of psoriatic plaques have been reported.The recall phenomenon has been reported in both radiation and solar damaged skin.Blood: Bone marrow depression, leukopenia, thrombocytopenia, pancytopenia, anaemia, hypogammaglobulinaemia, haemorrhage from various sites, septicaemia.Alimentary System: Gingivitis, pharyngitis, stomatitis, anorexia, vomiting, diarrhoea, haematemesis, melaena, gastrointestinal ulceration and bleeding, enteritis, hepatic toxicity resulting in active liver atrophy, necrosis, fatty metamorphosis, periportal fibrosis, or hepatic cirrhosis. In rare cases the effect of methotrexate on the intestinal mucosa has led to malabsorption or toxic megacolon.Hepatic: Hepatic toxicity resulting in significant elevations of liver enzymes, acute liver atrophy, necrosis, fatty metamorphosis, periportal fibrosis or cirrhosis or death may occur, usually following chronic administration.Urogenital System: Renal failure, azotaemia, cystitis, haematuria, defective oogenesis or spermatogenesis, transient oligospermia, menstrual dysfunction, infertility, abortion, foetal defects, severe nephropathy. Vaginitis, vaginal ulcers, and nephropathy have also been reported.Pulmonary System: Infrequently an acute or chronic interstitial pneumonitis, often associated with blood eosinophilia, may occur and deaths have been reported.Acute pulmonary oedema has also been reported after intrathecal use. Pulmonary fibrosis is rare.A syndrome consisting of pleuritic pain and pleural thickening has been reported following high doses.Central Nervous System: Headaches, drowsiness, blurred vision, aphasia, hemiparesis and convulsions have occurred possibly related to haemorrhage or to complications from intra-arterial catheterization. Convulsion, paresis, Guillain-Barré syndrome and increased cerebrospinal fluid pressure have followed intrathecal administration.Other reactions related to, or attributed to the use of methotrexate such as pneumonitis, metabolic changes, precipitation of diabetes, osteoporotic effects, abnormal changes in tissue cells, abnormal (usually 'megaloblastic') red cell morphology and even sudden death have been reported.There is the potential for Non-Hodgkin's lymphoma to develop through the use of methotrexate.There have been reports of leukoencephalopathy following intravenous methotrexate in high doses, or low doses following cranial-spinal radiation.Adverse reactions following intrathecal methotrexate are generally classified into three groups, acute, subacute, and chronic. The acute form is a chemical arachnoiditis manifested by headache, back or shoulder pain, nuchal rigidity, and fever. The subacute form may include paresis, usually transient, paraplegia, nerve palsies, and cerebellar dysfunction. The chronic form is a leukoencephalopathy manifested by irritability, confusion, ataxia, spasticity, occasionally convulsions, dementia, somnolence, coma, and rarely, death. There is evidence that the combined use of cranial radiation and intrathecal methotrexate increases the incidence of leukoencephalopathy.Acute or chronic interstitial pneumonitis, often associated with blood eosinophilia, may occur and deaths have been reported. (see Section 4.4 Warnings And Precautions for Use) | |