For some people struggling with depression, the idea of finding relief in a shop rather than a doctor’s surgery is appealing. Shelves lined with supplements promising calm, balance, and better sleep appear to offer a gentler path than prescription medication.

But do these over-the-counter (OTC) options actually work? Experts remain cautious.

According to one psychiatric specialist, the evidence supporting herbal remedies and dietary supplements for depression is weak. Most studies have been small, lacking the power to produce reliable results, even when pooled together.

"At present I would not recommend that patients rely upon these OTC products to help with depression," Glyn Lewis, professor of epidemiological psychiatry at University College London, told Medscape News UK.

He advised patients to seek medical guidance that includes non-pharmacological strategies, psychological support, and, where appropriate, pharmacological treatment.

Limited Evidence

The most comprehensive analysis to date came from a recent UK-led scoping review, published in Frontiers in Pharmacology. It examined 209 randomised controlled trials, with a median of just 70 participants each. Of these, 78 were conducted in Iran, 28 in Germany, 27 in the United States, 13 in Australia, and nine in the UK.

Researchers found “limited but promising” signals for ingredients such as folic acid, lavender, zinc, tryptophan, Rhodiola, and lemon balm. However, they stressed that further evaluation as adjuncts to established treatments is needed.

Lead investigator of the scoping review, Rachael Frost, senior lecturer in health and social care at Liverpool John Moores University, said the aim was to map evidence rather than deliver verdicts. “The most important limitation is that we didn’t look at the quality of the trials we included, only the volume,” she told Medscape News UK.

Risks for Patients

Stella Chan, professor of evidence-based psychological treatment at the University of Reading, warned that patients may misinterpret early findings.

“Promising results may not be good enough in this day and age when alternative treatments have been around for more than 50 years,” she said.

Dr Cosmo Hallstrom, a London-based general adult psychiatrist, added: “The real big danger is that depressed people will choose to go down the alternative treatment route when effective treatments and skilled practitioners are available.”

Joseph Firth, professor of psychology and mental health at the University of Manchester, agreed that biological risks are low but said patients could waste time and money or delay care.

Personalised Approaches

Firth suggested that future studies should examine personalised nutritional interventions rather than searching for a single “best” supplement. “This is because research is increasingly showing us how the nutritional status, absorption of certain nutrients, and impact of supplementation vary substantially across the population.

“Likewise, the causes, severity and symptoms of depression can be entirely different between two individuals with the same diagnosis”. Chan added that factors such as age, severity, and gender may also influence how people respond to supplements.

Barriers to Research

Hallstrom pointed out that limited funding and incentives makes it difficult to test supplements properly. “Good studies cost a lot of money to run, and those marketing health supplements tend not to have the money to spend. Their treatments are also not patented so there is little financial incentive,” he said. 

He added that sellers of herbal products are not required to demonstrate efficacy and can “say almost what they like.”

Last month, the Advertising Standards Authority (ASA) upheld a complaint against TRIP drinks over claims that its products were “science-backed”. The regulator found that statements suggesting the drinks could reduce stress and anxiety through ingredients such as lion’s mane, lemon balm, and chamomile breached advertising rules.

Hope for the Future?

Despite concerns, experts acknowledged potential benefits of OTC supplements if robust evidence emerges, such as finding previously undiscovered molecules that, if harnessed and modulated, could be beneficial. “That is the hope, but I think it is unlikely as none have emerged so far,” Hallstrom noted. 

“Mental health is stigmatised, and some have negative feelings about taking medications,” said Chan. “If OTC products could actually work, they could provide a more accessible and less stigmatised treatment option. The question is just whether they work.” 

Chan, Frost, and Hallstrom reported no relevant disclosures.

Annie Lennon is a medical journalist. Her writing appears on Medscape Medical News, WebMD, and Medical News Today, among other outlets.