Researchers have profiled the side effects reported by people taking methotrexate to provide patients with more information on what to expect.

The study by Manchester University of more than 1,000 patients from across the UK found that 77.5% had at least one side effect after taking the drug – most commonly gastrointestinal symptoms.

At six and 12 months, 89.5% and 84.4% of participants were still taking the immunosuppressant – which can be prescribed for conditions including rheumatoid arthritis, psoriasis and Crohn’s disease – although some had switched to the subcutaneous version.

The results published in Rheumatology found that around a quarter of the patients had just one symptom but 60% reported three or more.

Side effects included nausea (31%), diarrhoea (15%), fatigue (29%), headaches (19%), dizziness (12%), alopecia (9%) and mouth ulcers (12%).

The analysis also showed that older age was associated with less reporting of gastrointestinal side effects, whereas women were more likely to report gastrointestinal, mucocutaneous, or neurological side effects compared with men.

Researchers also found that alcohol consumption at the start of treatment was associated with nausea, alopecia, and mucocutaneous side effects while taking the drug.

Patients who had higher levels of concern about treatment also reported more gastrointestinal side effects, particularly nausea.

Dr Suzanne Verstappen, a reader in musculoskeletal epidemiology at The University of Manchester, said methotrexate had transformed the treatment of inflammatory arthritis but worries about side effects could stop patients from starting it or reduce adherence to treatment and having this information could help them make informed decisions.

‘These findings, however, provide patients and clinicians with insight into the management of patients with rheumatoid arthritis starting methotrexate.

‘Their concerns can be lessened by stressing the benefits of the treatment alongside a more specific discussion about side effects.’

This story was initially published on our sister title Pulse.