Millions of patients on antidepressants are being urged to check their tablets, after a manufacturing error led to two drugs being packaged incorrectly.
The Medicines and Healthcare products Regulatory Agency (MHRA) have warned sealed packets of sertraline may contain blister strips of citalopram.
Both of these drugs are selective serotonin reuptake inhibitors (SSRIs), commonly used to treat depression, anxiety and other mood disorders by boosting serotonin in the brain.
But taking the wrong drug by accident can have serious side-effects, the MHRA warns, requiring urgent medical attention.
Amarox Limited have now issued a precautionary recall of one batch of Sertraline 100mg film-coated tablets, with an expiry date of May 2028 and batch number V2500425.
Patients prescribed the drug are being urged to check their boxes contain the right medication, with blister strips matching the batch number and expiry date printed on the outer packaging.
‘If the blister strips inside the carton are labelled Citalopram 40mg, please contact your pharmacy as soon as possible,’ Dr Alison Cave, MHRA chief safety officer, said.
‘Patients who have accidentally taken citalopram instead of – or as well as – sertraline, may experience some heightened serotonergic side effects,’ she added.
Packets of sertraline 100mg film-coated tablets may incorrectly contain blisters of citalopram 40mg, health officials have warned
‘These can include nausea, headache, sleep changes and mild anxiety.’
Those who have been correctly prescribed sertraline 100mg do not need to take further action.
So far, the manufacturing company has received one complaint from an adult patient who reported the adverse event of a headache, where it was identified that their prescription wrongly contained a strip of Citalopram tablets.
Both drugs were manufactured at the same site, and the error appears to have occurred during secondary packing of the strips into the carboard packaging.
Pharmacists and other healthcare professionals involved in dispensing the antidepressant have also been advised to contact any patients who may have been given the wrong medication and request it be returned.
The affected batch was first distributed on 28 November 2025.
GPs and clinicians should then be made aware of the mix-up to discuss treatment review and whether a new prescription may be required for ongoing resupply.
Patients aged over 65 or under 18, as well as those with heart of liver conditions need to be particularly cautious, the MHRA have warned.
Any suspected adverse reactions should also be reported via the watchdog’s Yellow Card scheme.
The MHRA has advised healthcare professionals to stop supplying the affected batch and return all remaining stock to their suppliers.
More than eight million patients in England are prescribed the drugs to help with the likes of depression, anxiety and obsessive compulsive disorder.
SSRIs work by increasing levels of serotonin, a chemical in the brain that controls mood.
Sertraline needs to be taken once a day at the same time. Taking an extra dose can be dangerous – even if a pill has been missed.
