Methotrexate has been around as a treatment option for rheumatoid arthritis since the early 1970s. It is still one of the most commonly prescribed drugs for treating rheumatoid arthritis today.
Rheumatologists agree that it is one of the safest drugs for managing the condition despite some reports to the contrary. The bottom line is to take the dose of methotrexate that has been tailored for you, accompanied by periodic follow-up reviews with your treatment doctor.
Methotrexate belongs to a class of drugs known as disease-modifying anti-rheumatic drugs (DMARDs). These drugs curb the underlying disease process rather than simply treating the presenting symptoms. Methotrexate reduces the activity of the immune system (your body’s defence system), which is overactive in rheumatoid arthritis and other forms of inflammatory arthritis.
Oral methotrexate comes in two strengths: 2.5mg and 10mg tablets. To avoid confusion, only one strength (usually 2.5mg tablets) is used.
Methotrexate is usually taken as a single weekly dose on the same day every week. The recommended dose may be taken all at once or it may be divided into equal separate doses taken on the same day every week, if necessary.
Treatment is usually started with a very low dose of 5mg (two 2.5mg tablets) or 10mg (four 2.5mg tablets) a week, increasing to an average dose of 20mg per week. The dose is adjusted by your doctor depending on your response and it may be increased up to about 30mg once a week. Therefore, additional visits may be required to the physician at the treatment onset to tailor the correct dose for you.
The most common side effects associated with methotrexate are nausea, vomiting and diarrhoea. These can be avoided by dividing the recommended dose across the day instead of taking the tablets all at once. Taking the tablet dose after meals is also best.
NOTE: The divided dose is to be consumed on the same day. For example if the day’s dose is divided into 2, take after breakfast and dinner. Or if you divide it into 3, take each dose after every main meal if you have 3 meals per day.
Mouth ulcers and sores are other common side effects of methotrexate therapy. Many patients also complain of headaches, fatigue and an overall ‘blah’ feeling, sometimes called ‘methotrexate fog’. This happens more so on the day after you take the dose.
A 5mg folate tablet taken the day after your Methotrexate dose is the recommended treatment to manage these side effects. Folate tablets in 5mg strength can be purchased over the counter in most pharmacies.
Serious side effects can be reduced to a minimum by following these important instructions:
By Manu Arora
Arthritis & Osteoporosis NSW