The NHS is advising millions of people in the UK on antidepressants to steer clear of grapefruit and grapefruit juice due to potential risks that could amplify medication side effects or interfere with the drug’s effectiveness.
The warning comes as new figures show a steady rise in antidepressant prescriptions across the country, with more than 8.7 million people using these medications in the 2023/24 period, a 2.1% increase from the previous year.
Data from the NHS Business Services Authority (NHSBSA) shows that the prescription of antidepressants in the UK has soared, reaching a record 89 million items in the last year. This represents a 3.3% rise from the 2022/23 period.
The increase in prescriptions aligns with growing concerns around mental health, with many turning to medication to manage conditions like depression and anxiety.
Despite their widespread use, the exact mechanism by which antidepressants work remains somewhat unclear.
The NHS explained that these medications are thought to help by increasing the levels of neurotransmitters such as serotonin and noradrenaline, which play key roles in regulating mood and emotion.
However, they can come with a range of side effects, from dizziness and headaches to more serious symptoms like erectile dysfunction and reduced libido.
While side effects of antidepressants can vary, one common interaction of concern involves grapefruit.
Research shows that grapefruit and its juice can interfere with how some antidepressants are metabolized in the body, potentially leading to an increased level of the medication in the bloodstream.
This can heighten the risk of adverse side effects or reduce the medication’s effectiveness.
The interaction occurs because grapefruit blocks an enzyme called CYP3A4, which is crucial for breaking down many medications in the liver and small intestine.
When grapefruit inhibits this enzyme, it causes certain antidepressants to remain in the body for longer than intended, leading to an increased concentration of the drug.
This can amplify side effects, such as nausea, dizziness, or even more serious complications like heart rhythm problems or excessive sedation.
The NHS specifically warns patients taking selective serotonin reuptake inhibitors (SSRIs) and serotonin-noradrenaline reuptake inhibitors (SNRIs) to avoid grapefruit unless otherwise directed by a doctor.
These classes of antidepressants are commonly prescribed to treat depression and anxiety and include medications like fluoxetine, sertraline, venlafaxine, and duloxetine.
Additionally, patients on tricyclic antidepressants (TCAs), such as amitriptyline or nortriptyline, should also be cautious.
While grapefruit’s effect on TCAs is less well-documented, it’s advisable to err on the side of caution due to the potential for interactions with other medications patients might be taking.
Given the possible risks, the NHS advises anyone on antidepressants to consult their doctor or pharmacist about their diet and whether they should avoid grapefruit while taking medication.