What does St John's wort do? | HRI Good Mood | St John's wort flower

What does St John’s wort do, and how can it improve your mood and sleep?

St John’s wort is a traditional herbal medicine used to balance mood, reduce anxiety and promote better sleep. Here, we explain what St John’s wort does, how it works, and why it’s a gentler, yet powerful, natural alternative to pharmaceutical medication for treating low mood and mild anxiety.  

What is St John’s wort?

St. John’s wort is one of the most important plants in herbal medicine, recognised for its healing and protective qualities since classical antiquity. The herbaceous perennial gets its name from the fact that it often blooms on St John’s Day, or Midsummer’s Day. Its golden blossom looks like little suns with stamens that are like sunbursts. The radiant flowers are heliotropic, which means they follow the sun as it moves across the sky. The word wort derives from the Old English wyrt, meaning plant, root or herb.

What does St John’s Word do to the brain?

Research suggests that St John’s wort works in a similar way to commonly prescribed antidepressants, SSRIs* (selective serotonin uptake inhibitors) often known as Prozac, by ensuring the brain doesn’t use up all of its ‘feel good chemicals’. St John’s wort also inhibits the uptake of noradrenaline and dopamine, two other neurotransmitters that, like serotonin, produce feelings of happiness, pleasure and satisfaction.

The hypericin and hyperforin in St John’s wort’s leaves and flowers increase the activity of these neurotransmitters, and help the brain use them more effectively. As if that wasn’t enough, St John’s wort also maintains gamma-Aminobutyric acid (GABA), a natural brain relaxant that makes us feel good. When GABA levels get too low, it makes it hard for the body to recover from stress, leading to anxiety and insomnia.

What does St John’s wort do for a low mood?

St. John’s wort is best known as a treatment for low mood. A meta-analysis of 27 clinical trials concluded the herb has a similar level of effectiveness as SSRIs in treating mild-to-moderate depression.** The British Journal of Medicine published a similar review that found extracts of hypericum to be even more effective than placebo for the treatment of mild to moderately severe depressive disorders.***

There is strong and wide-reaching anecdotal evidence to support research in showing the difference St John’s wort can make to mental health.

“When I could no longer take SSRI’s due to side effects, I tried St John’s wort as an alternative. It’s definitely helped with my depression and my mood has lifted quite a lot.”

— Mind, mind.org.uk, “St John’s wort”

“Life seemed more bearable. I saw colour.”

— Mind, mind.org.uk, “St John’s wort”

What does St John’s wort do for anxiety?

While there are, as yet, relatively few long term studies on St John’s wort for anxiety treatment (versus depression), there is good evidence to suggest it can provide relief. This is logical given that the herb works on the GABA levels in the brain in a similar way to prescribed anxiety medications.

One study found that St John’s wort produced a positive shift in emotional responses towards negative signals. It found that after seven days of taking St John’s wort, participants had reduced attention to fearful facial expressions, results that also occur with other antidepressant treatments.****

Testimonials from the use of our St John’s wort product, HRI Good Mood demonstrate just how effective this product is for treating anxiety.

“These [tablets] have helped me feel calmer, happier and stable, easing my lifelong anxiety.”

— Holland & Barrett customer review

Another wrote:

“St John’s wort literally saved my life when I had postnatal depression and anxiety…  Miracle.”

— Holland & Barrett customer review

Depression, anxiety and sleep

Do you struggle to clear your mind as you try to drift off to sleep at night? Or perhaps you fall asleep quickly but wake in the night with racing thoughts?

Anxiety and depression are two sides of the same coin. They frequently co-exist, and a number of the symptoms overlap. This is because the same neurotransmitters are involved in anxiety and depressive disorders, which is why some medications are used to treat both conditions.

Disturbed sleep wreaks havoc with our mental and physical health. Anxiety more obviously creates stress and restlessness in the body that makes it harder to drift off to sleep. But low mood and depression can also be affected by, and affect, sleep quality. In fact, sleep disorders are a core symptom of depression, with around three quarters of depressed patients reporting insomnia.***** Sleep problems create a vicious circle in both depression and anxiety, worsening symptoms, like worry and dread, that, in turn, make it harder to fall and stay asleep. Restoring balance in mood and emotion during the day can help you to sleep better at night.

St John’s wort and the ‘sleep hormone’ melatonin

In addition to helping the body relax, and reduce reactions to stress and worry, St John’s wort assists with the production of melatonin by balancing the uptake of serotonin in the brain. Melatonin, the so-called ‘sleep hormone’, plays a central role in regulating our circadian rhythm or natural sleep–wake cycles.

Far fewer, less serious – if any – side effects

Although infrequent, some people experience minor side-effects from taking St John’s wort, such as upset stomach, dry mouth, headache, fatigue, dizziness, or sensitivity to sunlight. However, many people don’t experience any side effects at all. As with most medications, any reactions vary from person to person.

How long does St John’s wort take to work?

It may take 3 to 6 weeks to feel any effects from St. John’s wort, however, some people report feeling the effects within days. It’s vital you don’t stop taking St. John’s wort suddenly or all at once, as rapid withdrawal could cause unpleasant side effects.

How to take it

St John’s wort is most commonly sold in tablet form, like HRI’s Good Mood, which can help with slightly low mood and mild anxiety. It can also be found as a loose tea or tincture. However, it’s easiest to keep track of dosage if you take St John’s wort in a tablet or capsule and stick to one brand. Two HRI Good Mood tablets provide the strongest daily dose available on the UK market, while giving you the flexibility to take one a day for a gentler dose if preferred.

While St John’s wort helps with anxiety symptoms that interfere with sleep it shouldn’t be taken right before bed.


St John’s wort is an effective, natural way to balance mood and stress levels, improve overall well-being, and promote healthier, more regular sleep patterns over time. See your GP if you are struggling to manage a low mood. You can also reach out for other support via mind.org.uk.

Important note

Do not take St John’s wort with antidepressants. Always speak to your GP and/or pharmacist before stopping or reducing other anti-depression medications. Consult your GP or pharmacist for interactions between St John’s wort and other prescription or over-the-counter drugs, including but not limited to the contraceptive pill. St. John’s wort should not be used during pregnancy or while breastfeeding. Please read the Patient Information Leaflet before taking this product.

*Mind.org.uk. (2019). St John’s wort

** Ng X, et al. (2017)

***Linde et al (1996)

****Warren. M., Cowen. P. & Harmer. C.(2018).

*****Nutt D, Wilson S, Paterson L. (2008)

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