Could OTC Remedies Really Work for Depression?

 A recent scoping review in the UK reported that some over-the-counter (OTC) supplements showed “limited but promising” evidence for treating depression. Researchers identified folic acid, lavender, zinc, tryptophan, rhodiola, and lemon balm as ingredients deserving investigation. 

Further evaluation of herbal supplements as adjuncts to antidepressants and psychological therapies is needed, the researchers concluded.

“This is an interesting review but the evidence to support the effectiveness of herbal remedies or dietary supplements is still poor,” said Glyn Lewis, professor of epidemiological psychiatry at University College London, who was not involved in the study.

He told Medscape News UK: “Many of the trials are very small and therefore providing unreliable results, even in aggregate. At present I would not recommend that patients rely upon these OTC products to help with depression. It would be better to seek medical advice that would include non-pharmacological advice and treatment, as well as the possibility of pharmacological treatment.” 

Quality vs Quantity

Study investigator Rachael Frost, senior lecturer in health and social care at Liverpool John Moores University, told Medscape News UK: “The most important limitation is that we didn’t look at the quality of the trials we included, only the volume of clinical trials available.”

Frost added that the study’s aim was to scope the literature and map available evidence rather than make definitive conclusions on each product. 

The review, published in Frontiers in Pharmacology, included 209 randomised controlled trials, with a median of 70 participants each. Of these, 78 were conducted in Iran, 28 in Germany, 27 in the US, 13 in Australia, and nine in the UK. 

Stella Chan, professor of evidence-based psychological treatment at the University of Reading, said the study was useful but noted that narrative reviews cannot replace meta-analyses.

Vulnerable Population 

Chan also warned that patients with depression may misinterpret the findings and delay seeking evidence-based treatment.

“Promising results may not be good enough in this day and age when alternative treatments have been around for more than 50 years,” said Dr Cosmo Hallström, a London-based general adult psychiatrist. “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,” he told Medscape News UK. 

Joseph Firth, professor of psychology and mental health at the University of Manchester, noted that while biological risks of supplements are generally low, patients risk wasting time and money or delaying evidence-based care.

Personalised Approach

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,” he told Medscape News UK. “Likewise, the causes, severity and symptoms of depression can be entirely different between two individuals with the same diagnosis.” 

Different ages, severities, and genders may respond differently to different supplements, Chan noted.

Research Barriers

Hallström said that a lack of funding and incentives limits research on supplements. “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 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.

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,” Hallström 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 Hallström reported no relevant disclosures.

https://www.medscape.com/viewarticle/could-otc-remedies-really-work-depression-2025a1000mlo