Calambres y Espasmos

5-HTP is a direct precursor to serotonin, which is further converted to melatonin, making it mechanistically relevant to sleep onset. Animal research shows it shortens NREM sleep latency and restores sleep after serotonin depletion. Clinical evidence includes improved sleep stability in a crossover RCT in Parkinson's disease patients and reduced sleep terror frequency in children.

Ashwagandha (Withania somnifera) root extract has been used in Ayurvedic medicine for millennia as a Rasayana (rejuvenator) and sleep promoter. Multiple recent double-blind RCTs demonstrate significant improvements in sleep onset latency, total sleep time, and sleep efficiency, with the NIH ODS confirming this evidence.

Preclinical data show that both essential oil and saponin fractions of Semen Platycladi significantly shorten sleep onset time in PCPA-induced insomnia mice. The mechanism involves upregulation of serotonergic and GABAergic receptor systems. This supports the traditional TCM claim of biota seed as a sedative herb that facilitates sleep initiation.

California poppy has documented effects on sleep latency in human observational and animal studies. An open-label observational study (Abdellah et al., J Trad Complement Med 2019) using a combination with valerian in 36 insomnia patients showed significant reduction in insomnia severity and increased sleep duration after 4 weeks. Animal data show sleeping induction at doses above 100 mg/kg (Rolland et al. 1991). The EMA recognizes it as a traditional herbal medicine for mild sleep disturbances. A Phase 3 RCT (NCT06795776, 104 participants) has been conducted, though results are pending publication.

Chamomile (Matricaria chamomilla) is one of the most widely used traditional sleep herbs. Its key active compound, apigenin, binds to GABA-A receptors, producing sedative effects. RCTs in older adults and insomnia patients show modest improvements in sleep quality and sleep-onset-related parameters, though a pilot RCT in primary insomnia found moderate but non-significant sleep latency reductions.

Animal models demonstrate that P. cocos extracts reduce sleep latency and counteract caffeine-induced wakefulness, consistent with facilitation of sleep onset. The GABAergic mechanism of pachymic acid (BZD binding site activation) provides a plausible biological pathway for sleep onset facilitation.

GABA is the primary inhibitory neurotransmitter of the CNS and a central target for virtually all pharmacological hypnotic drugs. Exogenous GABA supplementation and GABA combined with L-theanine have been shown in controlled studies to decrease sleep latency and improve NREM sleep in animal and human research.

Preclinical studies demonstrate that Ganoderma extract significantly shortens sleep latency (time to fall asleep) through GABAergic and serotonergic mechanisms, and via gut microbiota-mediated serotonin signalling. Traditional Chinese medicine describes a sedative 'An-Shen' effect for insomnia.

Gastrodin's upregulation of endogenous GABA synthesis via GAD and sodium channel blocking properties are well-supported mechanisms for sleep-onset promotion in animal studies. Traditional use specifically cites GE for insomnia accompanying head tension. Evidence is predominantly animal-based.

Glycine is a non-essential amino acid that promotes sleep onset by acting on NMDA receptors in the suprachiasmatic nucleus to facilitate the core body temperature drop required for sleep initiation. Controlled clinical trials in humans show 3 g of glycine before bedtime significantly reduces sleep onset latency and improves subjective sleep quality with PSG confirmation.

Hops (Humulus lupulus) cone is approved by the German Commission E for sleep disturbances associated with anxiety or restlessness. It acts primarily via GABAergic mechanisms and has binding affinities for melatonin and serotonin receptors. Clinical evidence most consistently supports sleep improvement when combined with valerian, with sleep latency and quality significantly improved.

Jujube seed extract (Semen Ziziphi Spinosae) has the strongest evidence base of all jujube uses, grounded in both preclinical and small clinical studies. Key bioactive compounds spinosin and jujubosides modulate GABA-A receptors and the serotonin (5-HT1A) pathway, producing sedative effects. A review of pharmacological effects cited two small clinical studies supporting a role in insomnia management. Robust large-scale RCTs remain lacking.

A 3-week RCT in 21 middle-aged adults found that 25 mg/day Zembrin improved subjective sleep onset compared to placebo. Traditional use included giving fresh kanna juice to induce sleep in young children. Melatonin receptor activation has also been proposed as a contributing mechanism.

Kava (Piper methysticum) root contains kavalactones that modulate GABA-A receptors and voltage-gated sodium and calcium channels, producing anxiolytic and sedative effects. Clinical research shows decreased sleep latency, improved sleep quality, and anxiolytic benefits in insomnia; however, hepatotoxicity concerns limit its clinical recommendation.

Controlled clinical trials and polysomnographic studies demonstrate that 3 g of glycine before bedtime shortens sleep onset latency and reduces time to slow-wave sleep. The mechanism involves NMDA receptor-mediated activation in the suprachiasmatic nucleus, inducing peripheral vasodilation and a drop in core body temperature that facilitates rapid sleep initiation.

L-Theanine is an amino acid from tea (Camellia sinensis) that promotes relaxation without sedation by modulating glutamate and GABA receptors and increasing alpha brain wave activity. A 2025 systematic review and meta-analysis found L-theanine supplementation showed positive effects on subjective measures of sleep onset latency and overall sleep quality.

L-Tryptophan is the essential amino acid precursor to serotonin and melatonin. Clinical evidence shows it reduces the time to fall asleep at doses of 1 g or more. A meta-analysis of 18 studies found tryptophan supplementation significantly reduced wake-after-sleep-onset, and situational insomnia with difficulty falling asleep responded rapidly at various doses.

Lavender (Lavandula angustifolia) is approved by the German Commission E for sleep disturbances associated with anxiety. Oral lavender oil (Silexan, 80 mg) has demonstrated efficacy in multiple RCTs, improving sleep quality and reducing anxiety-related insomnia. Inhaled lavender aromatherapy also shows sleep-promoting effects across multiple populations.

Multiple clinical trials support lemon balm's ability to improve sleep onset and quality. Rosmarinic acid inhibits GABA transaminase, raising brain GABA levels and promoting sedation. Both solo extracts and valerian combinations have demonstrated statistically significant improvements in sleep parameters. The European Medicines Agency (EMA) and the German Commission E recognize lemon balm for nervous sleeping disorders.

Nelumbo nucifera seed extract has been shown to decrease sleep onset latency in rodent models through GABAergic mechanisms. Neferine synergizes with thiopental to enhance sleep induction. Traditional use in East Asia documents lotus seeds as an aid to falling asleep.

Magnesium is an essential mineral that regulates NMDA glutamate receptors and GABA-A receptors, both central to sleep regulation. A systematic review and meta-analysis found magnesium supplementation reduced sleep onset latency by 17.36 minutes versus placebo in older adults with insomnia, though evidence quality was rated low-to-moderate.

Honokiol and magnolol reduce sleep latency in preclinical models via GABA-A receptor modulation at the benzodiazepine site. Human evidence from combination-product RCTs (particularly the 634-woman and 89-woman menopausal trials) shows improved sleep initiation. Typical doses used in human studies range from 60–250 mg/day of standardized extract.

Melatonin is the most extensively studied natural sleep-onset agent. Multiple meta-analyses of RCTs confirm it reduces sleep onset latency (SOL) by approximately 7–10 minutes on average, with the largest effects seen in delayed sleep phase disorder (up to ~39 minutes SOL reduction). A dose-response meta-analysis of 26 RCTs found benefits peak at around 4 mg/day.

Preclinical studies demonstrate that Semen Platycladi (P. orientalis seed) essential oil and saponins significantly shorten sleep onset time in PCPA-induced insomnia mouse models. This effect is attributed to upregulation of serotonergic and GABAergic neurotransmission.

Passionflower (Passiflora incarnata) has traditional use as a sedative herb and demonstrates GABAergic activity. A double-blind placebo-controlled RCT of passionflower herbal tea showed significant improvement in subjective sleep quality in healthy adults. It is often combined with valerian and hops for sleep support, where the combination showed improved sleep latency.

Preclinical studies consistently show that P. tenuifolia polygalasaponins reduce sleep latency (time to sleep onset) in pentobarbital-treated and PCPA-induced insomnia mouse models, supporting the TCM use of Yuan Zhi for difficulty falling asleep.

Progesterone's metabolite allopregnanolone produces sedative effects in humans, facilitating sleep onset. Oral micronized progesterone produces sedation via GABA-A modulation, a mechanism replicated in multiple human pharmacology studies. This effect is leveraged clinically by prescribing oral micronized progesterone at bedtime.

Wang & Wang (2022) demonstrated reishi supplementation in 60 chronic insomnia patients significantly reduced sleep onset time (sleep latency). The 2026 SLEEP 8-week RCT also captured sleep onset as part of the ISI outcome, with reishi outperforming melatonin. GABAergic sedative-adjacent activity is the primary proposed mechanism for accelerating sleep onset.

Saffron (Crocus sativus) and its active compounds crocin and safranal have been evaluated in multiple RCTs for sleep quality. A 2025 large decentralized RCT found saffron extract (20–30 mg) significantly reduced insomnia symptoms versus placebo, with the most pronounced effects on sleep induction specifically.

Preclinical studies show A. julibrissin shortens sleep-onset latency in rodents. GABAergic and serotonergic mechanisms have been identified for several constituents. Traditional use as a sedative that aids the transition to sleep is well-documented in TCM.

The 2025 BlueCALM crossover RCT in primary insomnia patients showed improved sleep parameters, including sleep initiation, with 400 mg/day S. lateriflora extract versus placebo. GABAergic and cortisol-suppressive mechanisms provide biological plausibility for a sedative-onset effect.

The Leeds Sleep Evaluation Questionnaire used in the Hausenblas et al. (2024) RCT includes a sleep onset subscale; MgT supplementation showed benefits for ease of getting to sleep in adults with self-reported sleep problems. The GABAergic and NMDA-modulating mechanisms of brain magnesium are consistent with reduced sleep-onset latency.

Valerian (Valeriana officinalis) root extract has been used since antiquity for insomnia and nervous tension, and is approved by the German Commission E for sleep disturbances due to nervousness. Multiple RCTs and meta-analyses report improved sleep quality and reduced sleep latency, though evidence quality is variable. The 2020 systematic review and meta-analysis (Shinjyo et al.) found significant benefit across 36 RCTs.

Gardenia jasminoides is traditionally used in TCM formulas for insomnia, including Zhi-zi-chi decoction, for difficulty falling asleep associated with heart fire and restlessness. Preclinical evidence shows geniposide and gardenoside have sedative properties in animal models. The 2010 crocetin human trial did not measure sleep onset latency specifically.

Traditional TCM use of Polygala root includes facilitating sleep onset in insomnia. The root's GABAergic and serotonergic mechanisms, and its documented sedative properties in preclinical models, are directly relevant to the process of falling asleep.

Poppy preparations have been used across multiple traditional medicine systems to hasten sleep onset. Both opioid (P. somniferum) and milder sedative (P. rhoeas, E. californica) species are implicated. The California poppy supplement form shows preliminary human evidence in combination with valerian for reducing sleep latency.

Sceletium has an ethnobotanically documented history of use as a soporific. Historical records from 1898 describe fresh sceletium juice being given to young children to rapidly induce deep sleep. The sedative/hypnotic property is one of the plant's traditional roles, but no clinical trial has specifically measured sleep latency as a primary endpoint.

SJW has been used traditionally for insomnia and sleep disturbances. The available polysomnographic clinical data showed no significant improvement in sleep onset latency. Its traditional use for nervousness and restlessness underpins the historical sleep indication, especially where anxiety or low mood impairs sleep onset.