The team, which also assessed curcumin, the probiotic Duolac ProAP4 and artichoke extract among other hangover remedies, pointed to method limits or imprecise measurements that contributed to the low evidence quality.
This is despite some studies showing statistically significant improvements in hangover symptoms. The researchers also highlight no two studies report on the same hangover remedy and no results have been independently replicated.
“Hangover symptoms can cause significant distress and affect people’s employment and academic performance,” says lead author Dr. Emmert Roberts from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN), King's College London.
“Given the continuing speculation in the media as to which hangover remedies work or not, the question around the effectiveness of substances that claim to treat or prevent a hangover appears to be one with considerable public interest.
“Our study has found that evidence on these hangover remedies is of very low quality and there is a need to provide more rigorous assessment.
“For now, the surest way of preventing hangover symptoms is to abstain from alcohol or drink in moderation.”
Full remedy list
The review, which appears in the journal Addiction and involves teams from King’s College London and South London and Maudsley NHS Foundation Trust, assessed 21 placebo-controlled randomised trials.
Of the 21 studies, eight were carried out on male participants only. The research team adds that the studies were generally limited in their reporting of the nature and timing of alcohol used to assess the hangover cures.
In addition, there were notable differences in the type of alcohol consumed and whether it was alongside food.
The hangover remedy list in full includes curcumin, Duolac ProAP4 (probiotics), L-cysteine, N-Acetyl-L-Cysteine (NAC), Rapid Recovery (L-cysteine, thiamine, pyridoxine and ascorbic acid) and Loxoprofen (loxoprofen sodium).
Other remedies include SJP-001 (naproxen and fexofenadine), Phyllpro (Phyllanthus amarus), Clovinol (extract of clove buds), Hovenia dulcis Thunb. fruit extract (HDE), polysaccharide rich extract of acanthopanax (PEA) and red ginseng.
The team also include studies that looked at Korean pear juice, L-ornithine, prickly pear, artichoke extract, 'Morning-Fit' (dried yeast, thiamine nitrate, pyridoxine hydrochloride, and riboflavin), propranolol, tolfenamic acid, chlormethiazole, and Pyritinol.
Meta-analysis not possible
“Of the limited interventions studied in placebo-controlled randomised trials no two studies reported on the same intervention. As such meta-analysis was not possible,” the team points out.
“Whilst there was evidence of statistically significant improvements across a range of alcohol-induced hangover symptoms when comparing placebo to clove extract, tolfenamic acid, pyritinol, Hovenia dulcis fruit extract, L-cysteine, red ginseng and Korean pear juice, all evidence was of very low quality.
The team go on to comment that whilst several studies report a lack of clear evidence for an effect of their studied intervention when compared to placebo, these estimates were also of very low quality.
“There did not appear to be any concerns regarding tolerability of any studied intervention, although only seven of the included trials (35%) reported the frequency of either Adverse Events (AEs) or Severe Adverse Events (SAEs).”
Published online: https://doi.org/10.1111/add.15786
“The efficacy and tolerability of pharmacologically active interventions for alcohol-induced hangover symptomatology: A systematic review of the evidence from randomised placebo-controlled trials.”
Authors: Emmert Roberts et al