Insomnia — difficulty falling asleep, staying asleep, or waking too early — affects approximately one in three Irish adults at some point, with approximately 10% experiencing chronic insomnia (symptoms at least three nights per week for three months or more). Despite its prevalence, insomnia is significantly undertreated: many people suffer in silence, use alcohol as a sleep aid (which worsens sleep quality), or cycle through various supplements without a clear framework for what evidence supports.
This guide provides a clear evidence hierarchy: sleep hygiene and behavioural interventions come first (strongest evidence, no side effects), followed by the supplements with the best clinical data.
Cognitive Behavioural Therapy for Insomnia (CBT-I) is the single most evidence-supported treatment for chronic insomnia — superior to sleeping pills in the long term, with effects that persist after treatment ends. CBT-I addresses the thought patterns, behaviours, and arousal responses that perpetuate insomnia. It includes: sleep restriction therapy, stimulus control, relaxation training, and cognitive restructuring of unhelpful beliefs about sleep.
Core sleep hygiene principles with strong evidence: maintain consistent sleep and wake times seven days per week (circadian anchor); avoid screens for at least one hour before bed (blue light suppresses melatonin secretion); keep your bedroom cool (around 18°C), dark, and quiet; avoid caffeine after 2pm; avoid alcohol as a sleep aid (it fragments sleep architecture, reducing restorative slow-wave sleep); regular exercise improves sleep quality, but vigorous exercise within 2 hours of bedtime may delay sleep onset in some people.
If you have chronic insomnia, the Sleepio app (CBT-I based, validated in RCTs, now available via some Irish GP practices) or a referral to a sleep psychologist is the most effective pathway. No supplement replaces this.
Valerian (Valeriana officinalis) is the most widely studied herbal sleep remedy, with over 30 clinical trials examining its effects. The primary active mechanisms involve valerenic acid (which modulates GABA-A receptors, increasing GABA activity) and isovaleric acid. The overall evidence is mixed: some trials show significant benefit, others show no effect over placebo. A 2006 systematic review in the American Journal of Medicine concluded that valerian may improve sleep quality without producing side effects, but the evidence is not sufficiently consistent to draw firm conclusions. Many practitioners find it clinically useful despite this.
The most common problem in valerian research is low-quality standardisation — different products contain vastly different amounts of active compounds. Look for extract standardised to valerenic acid content (≥0.4%). LI 156 (Sedonium) and Ze 91019 (Valdispert Forte) are specific extracts with the best clinical trial backing. Typical dose: 300–600mg standardised extract taken 1 hour before bed. Valerian is most effective with regular use (1–4 weeks) rather than as a single-dose acute remedy.
Passionflower is a beautiful climbing vine with an ancient traditional use as a sedative in North and South America. Its calming effects are mediated by flavonoids (particularly chrysin) that act on GABA-A benzodiazepine receptor sites, and by harmane alkaloids that are mild MAO inhibitors. A 2011 RCT in Phytotherapy Research found that passionflower tea significantly improved subjective sleep quality compared to placebo, particularly for sleep quality and waking. A 2017 pilot RCT found passionflower reduced anxiety-related sleep disturbance compared to placebo. Passionflower is frequently combined with valerian in products such as Dormeasan (A.Vogel) and various Pukka night-time blends widely available in Irish health shops.
Magnesium plays a critical role in sleep regulation — it activates the parasympathetic nervous system (rest and digest mode), regulates GABA receptor activity, and is involved in the production of melatonin. Magnesium deficiency is common in Ireland (particularly among older adults, those with high stress, regular alcohol users, and people on proton pump inhibitors). A 2012 double-blind RCT in the Journal of Research in Medical Sciences found that 500mg magnesium daily for 8 weeks significantly improved multiple sleep parameters in elderly subjects with insomnia, including sleep time, sleep efficiency, and serum melatonin levels. Magnesium glycinate is the best-absorbed form — 200–400mg at bedtime.
Melatonin requires a prescription in Ireland and cannot legally be purchased over-the-counter in Irish pharmacies. See our dedicated melatonin guide for a full explanation of the legal situation, why Ireland differs from the UK and US, and what alternatives are available. Brief answer: melatonin is most evidence-supported for circadian rhythm disruption (jet lag, shift work) rather than primary insomnia, and is available on prescription from your GP.
L-theanine is an amino acid found almost exclusively in green tea. It promotes relaxation without sedation by increasing alpha brain wave activity and modulating GABA, serotonin, and dopamine pathways. A 2019 randomised controlled trial in Nutrients found 200mg L-theanine daily for 4 weeks significantly improved sleep latency, sleep quality, and daytime alertness in boys with ADHD. Multiple trials in healthy adults have found benefits for reducing sleep disturbance. It pairs well with magnesium for anxiety-related insomnia. Dose: 100–400mg at bedtime, or as a green tea habit (150–200mg per cup).
| Claim | Evidence Level | Source |
|---|---|---|
| CBT-I: most effective insomnia treatment, outperforms medication long-term | Strong | Multiple Cochrane reviews; NICE guidelines |
| Valerian may improve sleep quality — evidence inconsistent | Moderate | Am J Med 2006 (systematic review) |
| Passionflower tea improves subjective sleep quality | Moderate | Phytother Res 2011 (RCT) |
| Magnesium 500mg improves sleep in elderly insomnia | Moderate | J Res Med Sci 2012 (RCT) |
| L-theanine reduces sleep disturbance | Moderate | Nutrients 2019; multiple RCTs |
| Melatonin for primary insomnia | Weak – better for circadian disruption | Cochrane 2002; requires prescription in Ireland |
All herbs listed here may potentiate sedative drugs including benzodiazepines, Z-drugs (zopiclone, zolpidem), antihistamines, and opioids — do not combine without medical guidance. Valerian: avoid in pregnancy and children under 3; do not drive or operate machinery within 4 hours of taking. Passionflower: avoid in pregnancy; theoretical interaction with MAOIs. Magnesium: may cause loose stools at high doses; use glycinate form. L-theanine: very safe, minimal known interactions.
If insomnia has persisted for more than 4 weeks and is affecting daytime functioning, mental health, or quality of life, see your GP. Insomnia is often secondary to other conditions — depression, anxiety, sleep apnoea, restless leg syndrome, pain, thyroid disorders — that require specific treatment. Your GP can refer you for CBT-I or prescribe short-term medication as a bridging measure while CBT-I takes effect.
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