
Does methotrexate cause weight gain?
Methotrexate belonging to the class of drugs known as antimetabolites is used in the treatment of various conditions, including cancer, autoimmune diseases, and certain types of inflammatory conditions. Medications that are typically prescribed for some of the above conditions often end up with certain undesirable outcomes. This includes weight gain, and a common question among patients on methotrexate is – does methotrexate cause weight gain? Following subsections offer a detailed look at the drug, including answers to the above question.
Conditions treated by methotrexate
Available in different formulations, including oral tablets, injectable solutions, and subcutaneous injections, the drug is commonly prescribed for treating the following conditions:
- Cancer treatment: Methotrexate is commonly used in the treatment of certain types of cancer, such as leukemia, lymphoma, and solid tumors like breast, lung, and head and neck cancers. It works by inhibiting the growth and division of cancer cells, thereby slowing down or stopping the progression of the disease.
- Autoimmune diseases: Methotrexate is frequently used to manage autoimmune diseases such as rheumatoid arthritis, psoriasis, and psoriatic arthritis. In these conditions, it helps to suppress the immune system and reduce inflammation. Methotrexate is often used as a first-line treatment for rheumatoid arthritis, either alone or in combination with other medications.
- Ectopic pregnancy: Methotrexate can be used as an alternative to surgery in the treatment of ectopic pregnancy. It works by stopping the growth of the developing embryo, allowing the body to reabsorb it without the need for surgical intervention in certain cases.
- Inflammatory bowel disease: Methotrexate is sometimes used as a treatment for Crohn’s disease and ulcerative colitis, the two main forms of IBD. It helps to reduce inflammation in the gut and control symptoms associated with these conditions.
Mechanism of action of methotrexate
The mechanism of action of methotrexate involves various pharmacological effects:
- Inhibition of dihydrofolate reductase: Methotrexate acts as a competitive inhibitor of the enzyme dihydrofolate reductase, involved in the synthesis of tetrahydrofolate, a crucial coenzyme required for the synthesis of nucleotides. By inhibiting DHFR, methotrexate disrupts the production of THF, leading to a decrease in nucleotide synthesis and impaired cell division.
- Disruption of purine and pyrimidine synthesis: Methotrexate’s inhibition of DHFR results in reduced levels of THF, leading to a deficiency of precursors necessary for the synthesis of purine and pyrimidine bases. As a result, methotrexate interferes with DNA and RNA synthesis, inhibiting cell proliferation.
- Anti-inflammatory effects: Methotrexate exhibits immunosuppressive and anti-inflammatory properties, particularly in the treatment of autoimmune diseases. It modulates the immune response by reducing the production of inflammatory cytokines, and this decreases inflammation and alleviate symptoms in conditions like rheumatoid arthritis and psoriasis.
- Enhanced adenosine release: Methotrexate has been found to increase the extracellular levels of adenosine, an endogenous molecule with anti-inflammatory properties. Adenosine acts on specific receptors and contributes to the immunosuppressive and anti-inflammatory effects of methotrexate.
Side effects of methotrexate
Methotrexate can cause a range of side effects, and the intensity may vary from person to person. Common side effects of methotrexate include the following:
- Gastrointestinal symptoms: Nausea, vomiting, loss of appetite, and diarrhea are common side effects of methotrexate. These symptoms are usually managed by consuming medication with food.
- Mouth sores: Methotrexate can cause ulcers or sores in the mouth or throat, causing discomfort or difficulty in eating or swallowing.
- Fatigue: Feeling tired or experiencing a lack of energy is a common side effect of methotrexate.
- Hair loss: Methotrexate can cause temporary hair loss or thinning, although hair usually regrows after the treatment ends.
- Skin reactions: Some individuals may experience skin reactions such as rash, itching, or sensitivity to sunlight.
- Liver toxicity: Methotrexate can affect liver function, and regular monitoring of liver enzymes is typically carried out during treatment. In rare cases, severe liver toxicity can occur, and immediate medical attention should be sought if symptoms such as jaundice or abdominal pain develop.
- Suppression of the immune system: Methotrexate suppresses the immune system, which can increase the risk of infections.
- Blood disorders: Methotrexate can cause a decrease in blood cell counts, including red blood cells, white blood cells, and platelets. Regular blood tests are typically carried out to monitor these levels.
Does methotrexate cause weight gain?
Weight gain is not a commonly reported side effect of methotrexate. On the contrary, weight loss or a stable weight is more commonly observed with methotrexate use. However, it’s important to note that individual responses to medications can vary, and a section of individuals may experience weight changes as a result of various factors, including the underlying condition being treated.
There are a few considerations related to weight and methotrexate:
- Nausea and loss of appetite: Methotrexate can cause nausea and loss of appetite, which may lead to temporary weight loss in some individuals. However, this is different from weight gain.
- Corticosteroid combination: In some cases, methotrexate may be used in combination with corticosteroids, such as prednisone, for certain conditions. Corticosteroids can cause weight gain as a side effect, but this would be attributed to the corticosteroid component rather than methotrexate itself.
- Disease-related factors: The underlying disease being treated with methotrexate, such as rheumatoid arthritis or psoriasis, can have effects on weight and metabolism. The disease itself or other factors related to the condition may contribute to weight changes.
How to prevent and deal with weight gain due to methotrexate?
Simple methods that help prevent and deal with weight gain include the following:
- Consume a nutritious and well-balanced diet that includes plenty of fruits, vegetables, whole grains, lean proteins, and healthy fats. Avoid excessive intake of processed foods, sugary beverages, and high-calorie snacks. Portion control and mindful eating can also be beneficial.
- Engage in regular physical activity to help maintain a healthy weight. Choose activities that can be incorporated into routine, such as walking, cycling, swimming, or strength training exercises.
- Monitor daily caloric intake to ensure that excess calories are not consumed.
- Drink adequate amount of water throughout the day. Sometimes, thirst can be mistaken for hunger, leading to unnecessary snacking or overeating. Staying hydrated may help prevent such situations.
Stress can contribute to emotional eating or unhealthy food choices. Practicing relaxation techniques, engage in hobbies, or mental health professional to manage stress.