Methotrexate contraindications and warnings


Following is information on contraindications to the use of methotrexate in general, pregnancy & amp; Breastfeeding and children. Please note that the contraindications may vary depending on the dosage form of a drug (eg tablet, syringe, ointment).

When should Methotrexate not be used?

Methotrexate should only be prescribed by physicians who have sufficient experience.

Methotrexate may not be used at

  • Renal impairment (creatinine clearance below 60 milliliters / minute)
  • liver damage
  • Diseases of the hematopoietic system (bone marrow)
  • increased alcohol consumption
  • an immune deficiency disease and severe infections
  • gastric ulcers and intestinal ulcers.

Before the start of therapy, the following check-ups should be carried out: complete blood count of the blood clotting cells, special liver values, certain red blood cell parts, renal function values and hepatitis blood count.

Methotrexate may only be given under strict benefit-risk assessment of the physician :

  • Limitation of lung function
  • Insulin-dependent diabetes mellitus
  • dormant chronic infections
  • Conditions leading to drainage
  • Risk factors such as impaired kidney function
  • Patients in old age
  • folic acid deficiency
  • Vaccination with live vaccines.

What should you watch out for during pregnancy and lactation?

The administration of methotrexate causes malformations in humans during the first trimester of pregnancy. Women should not get pregnant during treatment. It is essential to have a pregnancy test before treatment. If pregnancy occurs during treatment, or if the doctor considers it necessary to treat a pregnant patient, medical advice should be provided on the risk of adverse effects to the child associated with the treatment.

Methotrexate also damages the genetic material. Therefore, men treated with methotrexate are advised not to father a child during treatment and six months thereafter. Because of the possibility of subsequent serious serious disturbances of sperm production by methotrexate, it should be considered before starting therapy to store semen for later artificial insemination.

Methotrexate passes into breast milk. If the doctor considers a treatment with the drug to be unavoidable, it should be weaned.

What should be considered in children?

So far, there has not been sufficient experience with the use of methotrexate in children with cancer. For the active ingredient there are therefore no binding dosage recommendations for this age group and therapy.

Only for children and adolescents under 16 with polyarthritic forms of juvenile joint inflammation there is a dosage recommendation.

Warnings and Precautions

  • Cancer treatment with the drug should only be done by physicians experienced in tumor therapy and depending on the body surface.
  • During the treatment and especially when combining the medicine with the antibiotic trimethoprim, the blood count should be monitored regularly.
  • Because of the drug’s liver toxicity, do not take any more liver-damaging medication or drink alcohol during treatment.
  • In patients with impaired renal function, the physician must select lower dosages and check the kidney function continuously.
  • If ulcers, diarrhea, vomiting of blood or blood in the stool occur during treatment with the medicine, contact the doctor immediately.
  • Folic acid deficiency increases the toxicity of the drug. Therefore, folic acid supply should be ensured during treatment.
  • If irritable cough, fever, cough, chest pain or shortness of breath occurs during treatment with the medication, seek medical advice immediately.
  • The function of the liver and kidneys should be checked by a doctor during treatment.
  • If vomiting or diarrhea occurs during treatment with the drug, treatment should be discontinued until the end of these symptoms.
  • In case of skin and mucous membrane contact with the drug should the affected areas
    Rinse immediately with plenty of water.
  • The drug should only be used once a week to treat rheumatic diseases and psoriasis.
  • The active substance may affect the reactivity to such an extent that the active participation in the traffic or the use of machinery are dangerous. This applies to a greater extent in conjunction with alcohol.
  • The drug can attenuate vaccine reactions and falsify the results of laboratory tests.

Sometimes medications release allergic reactions.
If you notice any signs of allergic reaction, tell your doctor or pharmacist immediately.