Does St John’s wort improve mood?
St. John's wort is increasingly recommended to treat mood disorders like depression and anxiety. Clinical trials support its use for this and reveal that it is more effective than placebo in alleviating mild-moderate depression. Hypericin, hyperforin and flavonoids are some of the plant compounds which are considered responsible for helping it to improve mood.
How does St. John’s wort work?
In a healthily functioning nervous system, the amount of neurotransmitters (substances that helps to transmit nerve messages across the synapses between nerve cells) will be carefully balanced. Some enzymes metabolise neurotransmitters to avoid a build-up, whilst other substances such as monoamine oxidase inhibitors (MAOIs) balance this by increasing the presence of neurotransmitters.
One suspected cause of consistent low mood is thought to be an abnormality in the amount of neurotransmitters available, either from a lack of sufficient neurotransmitters at critical synapses in the brain, or as a result of abnormalities in the receptors themselves. Conventional antidepressants, such as MAOIs, work to help correct this.
St. John's wort is thought to have mild MAO-inhibiting properties and seems to inhibit serotonin uptake, which is the basis on which SSRI antidepressant medications work. Additionally, St John's wort appears to inhibit the uptake of the neurotransmitters dopamine, noradrenaline and glutamate, as well as the inhibitory neurotransmitter GABA, providing a balancing effect on the nervous system overall.(1)
What makes St. John’s wort good for mood?
A whole range of St John's wort's constituents have been investigated, with interest focusing mainly on the bioflavonoids, such as hypericin, pseudo-hypericin and hyperforin. A variety of these constituents have been credited for the plant's mood-enhancing effects at different times; but recently it has become clear that a combination of constituents needs to be present in order for St. John's wort to be of benefit. While St. John's wort is one of the most extensively researched herbs, still some of its constituents haven't even been fully investigated or understood yet. Therefore, holistically standardised extracts containing all the plant's constituents are more likely to be effective for enhancing mood.(2)
How to take St. John’s wort
St. John's wort is available in many formats. It can be taken internally as liquid drops/tincture, or tablets.
It can also be applied externally to the skin in the form of oils or creams. This method of application is used for treating shingles, neuralgia, pinched nerves (e.g. Carpal tunnel syndrome), and injuries to areas rich in nerves.
Always follow the manufacturer's guidelines when taking St. John's wort, and stick to the dose recommended on the packaging. Taking higher doses doesn't mean it will work better. The recommended dose is found to give best efficacy so stick with that.
How long does it take to work?
St. John's wort should be taken consistently over a period of time to see benefits. It could take between 4 and 8 weeks to see the full effect, so consistency is key.
Are there any side effects to be aware of?
In research on St. John's wort, the only side effects noted have been some gastrointestinal disturbances. It appears to cause no problems with driving, operating machinery, or drinking. The side effects of St. John's wort extracts are generally less than those reported in double-blind studies for non-phytopharmaceuticals.
Are there any precautions to take when taking St. John’s wort?
St. John's wort is not suitable for anything more than mild low mood in adults. Anything over and above mild low mood and anxiety is not suitable for self-medicating.
It happens rarely, but St. John's wort can raise photosensitivity levels. It's therefore best not to go lie in the sun for hours while you are taking it. You may get a heat rash or other skin response, which will go away once you're out of the sun, but may be alarming. So, cover up!
St. John's wort can also interfere with prescription drugs, so it is advised not to take St. John's wort if you are on any prescription medication.(3)
