The claimant, a retired teacher, developed a limb tremor in 2006. The defendant treated the claimant between 2007 and 2012 and prescribed a dopamine agonist.

The claimant stated that the medication resulted in her overindulging in online shopping to the extent that she placed 200 bids on eBay during the course of one night. She said that her behaviour became compulsive in nature and that she became obsessed with certain activities which resulted in her being unable to sleep for up to 48 hours. She alleged that the defendant failed to provide her with sufficient information regarding the side effects and risks associated with the consumption of the drug. She also claimed that she was not informed of any alternative options which were available to her.

The claimant’s expert, a consultant neurologist who specialised in movement disorders, testified that by 2010, it had become mandatory for warnings about Impulse Control Disorder (ICD) to be given to patients using the drug and that the risk of obsessive behaviour occurring should have been mentioned to the claimant.

The court held that the side-effects of the drug posed a material risk and the defendant was in breach of his duty in failing to give warning to the plaintiff of potential behavioural changes during consultations with her in 2010 and 2011. If the defendant had properly recommended that the plaintiff either reduce or discontinue her use of the drug, she would not have suffered from the psychosis that ensued.

A letter from the claimant’s nurse to the defendant was of significance. The claimant had expressed her concern to the nurse who suspected that she was suffering from ICD. The nurse, with the claimant’s permission, wrote a letter to the defendant expressing her views.

The judge decided that the defendant ought to have taken the letter more seriously and discussed the details of the claimant’s symptoms at their next consultation.

The defendant’s actions fell below the required standard of care and he was held liable for the harm caused, despite the defendant having acted in good faith.

The case is Hazel Kennedy v Dr Jonathan Frankel [2009] EWHC 106 (QB) (25 January 2019).