Proco sells three products people use for sleep. Sleep Formula has 2mg of melatonin and is the only one of our blends with every dose on the label. Sleep Support has 10mg of melatonin and a broader 14-ingredient blend, including St John's Wort, with undisclosed doses. Magnesium Glycinate has no melatonin: just 275mg of magnesium. Pick one of the two sleep blends, never both.
The evidence for all three is real but modest. If your sleep trouble has lasted for months, a supplement is not the first step. Guidelines put cognitive behavioural therapy for insomnia (CBT-I) first.
This page is written for US readers. Melatonin is a prescription-only medicine in Ireland and the UK.
Melatonin's effect is consistent, but small. A 2013 meta-analysis pooled 19 placebo-controlled trials in 1,683 people with primary sleep disorders. On melatonin, people fell asleep about 7 minutes faster and slept about 8 minutes longer than on placebo. Overall sleep quality improved slightly. The authors noted the benefit was smaller than for prescription sleep medicines.
Past a point, more is not better. A 2024 dose-response analysis of 26 randomised trials (1,689 observations) found the effect grew with dose, peaking at about 4mg a day. Timing mattered too: the gap between taking melatonin and going to sleep predicted how quickly people fell asleep.
That puts our two blends on either side of the line:
The US National Institutes of Health says short-term melatonin use appears safe for most people. Long-term safety information is lacking. In the US, melatonin is sold as a dietary supplement, which is regulated less strictly than a drug. Our melatonin dose-response explainer goes further.
Every amount is on the label: valerian 150mg, chamomile 100mg, GABA 100mg, L-tryptophan 100mg, lemon balm 100mg, passion flower 100mg and melatonin 2mg.
Disclosure lets you judge the evidence for yourself, and some of it is weak. Valerian is the best-known herb here. A 2024 umbrella review of eight systematic reviews found no evidence that valerian works for insomnia. It did find subjective improvements in sleep quality, but not on objective measures. The authors rated the underlying studies as low quality.
A caution on L-tryptophan. The UK prescribing information for a licensed L-tryptophan medicine (Optimax) warns that combining L-tryptophan with SSRI antidepressants could lead to serotonin syndrome. It says the same potential exists with SNRIs such as duloxetine, and that L-tryptophan may enhance the side effects of MAOI antidepressants. That medicine is dosed far higher than the 100mg in Sleep Formula. Even so, if you take an antidepressant, talk to your prescriber before taking Sleep Formula. More in L-tryptophan, sleep and serotonin.
Sleep Support pairs 10mg of melatonin with a 905mg blend of 14 ingredients. They include chamomile, passion flower, lemon balm, L-theanine, GABA, L-tryptophan, 5-HTP, St John's Wort and ashwagandha root. None has a disclosed dose, and our manufacturer has told us those amounts cannot be published. Its 13mg of magnesium is a token amount. If magnesium is what you want, take it on its own.
St John's Wort interacts with many medicines. The NIH says it can interact in dangerous, sometimes life-threatening ways. It can weaken birth control pills, warfarin, ciclosporin (used after transplants), some seizure medicines, some HIV and heart medicines, and some antidepressants. Combined with antidepressants or other drugs that affect serotonin, it may cause serious serotonin-related side effects. The NIH also says it may be unsafe in pregnancy. Sleep Support's label adds a warning on 5-HTP with antidepressants and triptans.
If you take any prescription medicine, talk to your doctor or pharmacist before taking Sleep Support. Our St John's Wort explainer covers the interactions in detail.
Each three-capsule serving gives 275mg of elemental magnesium from magnesium glycinate.
The most relevant trial is small and recent. In 2025, 155 healthy adults who reported poor sleep took 250mg of magnesium as bisglycinate, or a placebo, for four weeks. Insomnia Severity Index scores fell 3.9 points with magnesium and 2.3 with placebo (p=0.049). The authors called the effect small (Cohen's d 0.2). Other questionnaire measures, including perceived stress, did not differ from placebo. Sleep was self-reported, not measured objectively. We cover it in more depth in magnesium and sleep: what a new trial found.
Older evidence is weaker. A 2021 meta-analysis pooled three trials in 151 older adults with insomnia. On magnesium, people fell asleep about 17 minutes faster than on placebo. Total sleep time did not improve significantly. The authors rated the evidence low to very low quality.
The NIH sets an upper limit of 350mg a day of magnesium from supplements for adults. High intakes can cause diarrhoea, nausea and cramping. The risk of too much magnesium is higher if your kidneys do not work well. Magnesium can also affect how some antibiotics and osteoporosis medicines are absorbed.
US orders ship free, and a 90-day money-back guarantee covers your first order.
No. Together they give 12mg of melatonin, three times the studied peak of about 4mg. They also share several ingredients, including GABA, L-tryptophan, chamomile, passion flower and lemon balm. Choose one for the night.
Not on the current evidence. The 2024 dose-response analysis found the benefit peaked at about 4mg a day. That is why we are open that Sleep Support's 10mg sits above the studied peak.
Talk to your prescriber before taking any of them. Sleep Support contains St John's Wort, 5-HTP and L-tryptophan, which can all interact with serotonin-affecting medicines. Sleep Formula contains L-tryptophan. Magnesium Glycinate contains none of these, but your prescriber should still know about it.
These pages are for US readers. Melatonin is a prescription-only medicine in Ireland and the UK. The Food Safety Authority of Ireland says it is not permitted in food supplements there. The NHS says melatonin supplements are not authorised for sale in the UK.
These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.
This page is general information, not medical advice. Talk to your doctor or pharmacist before starting a supplement, especially if you take medication, are pregnant or breastfeeding, or have a health condition.
Last updated: November 2026