LONDON (Reuters) - British consumer products group Reckitt Benckiser is recalling all its over-the-counter painkiller Nurofen Plus in the UK after some packs were found to contain an anti-psychotic drug or an epilepsy medicine.

The Medicines and Healthcare products Regulatory Agency (MHRA) issued a safety alert late on Friday saying some Nurofen Plus packs had been found to have 50mg tablets of AstraZeneca's schizophrenia drug Seroquel XL in them, while others contained strips of 100mg capsules of Pfizer's epilepsy drug Neurontin.

"Reckitt Benckiser Ltd is now recalling all remaining unexpired stock of Nurofen Plus tablets in any pack size as a precautionary measure," the MHRA said in a statement.

Seroquel XL is a prescription-only drug used to treat serious psychiatric disorders including schizophrenia and bipolar disease, while Pfizer's Neurontin is an anticonvulsant prescribed for patients with epilepsy and severe migraine.

Nurofen Plus is a popular painkiller containing codeine that needs no prescription.

The MHRA first issued a safety alert on Thursday after receiving reports of Seroquel XL tablets in three different batches of Nurofen Plus.

Some patients reported having mistakenly taken the Seroquel, it said. Medical experts said a single dose of Seroquel XL was unlikely to cause major problems for a healthy adult.

In Friday's recall alert, Ian Holloway from the MHRA's Defective Medicines Report Centre (DMRC) said people should check to see if they have any packets of Nurofen Plus.

"If you do, return them to your nearest pharmacy," he said.