sleep
13 interactions related to sleep
propranolol + melatonin
Propranolol blocks the beta-adrenergic signal the pineal gland uses to make melatonin at night, lowering the body's own nighttime melatonin.
lemon balm + valerian
Lemon balm (Melissa officinalis) and valerian (Valeriana officinalis) both act on the brain's GABA system but at different points — valerian's valerenic acid nudges the GABA-A receptor while lemon balm's rosmarinic acid slows the enzyme that breaks GABA down — and the combination has been used as a gentle aid for restlessness and sleep difficulty. The effect is mild rather than pharmaceutical.
caffeine + ashwagandha
Caffeine is a stimulant that raises alertness and cortisol; ashwagandha is an adaptogenic herb that, taken on its own, modestly lowers cortisol and perceived stress in human trials. People combine them hoping ashwagandha will take the edge off caffeine's jitters. That pairing is plausible but has not been tested directly in humans, so the 'calm focus' benefit remains theoretical rather than proven. The combination is generally well tolerated in healthy adults.
calcium + magnesium
Calcium and magnesium work together in bone mineralization, muscle contraction, and nerve signaling. They share some intestinal absorption pathways, so very large single doses of one can modestly reduce uptake of the other. A balanced intake of both, weighted toward food, supports bone health better than emphasizing calcium alone.
ashwagandha + magnesium
Ashwagandha helps dampen the body's stress-hormone response while magnesium supports the relaxation and nervous-system pathways that let the body wind down. The two act on different parts of the stress-and-sleep system, but no human trial has tested the specific combination, so any added benefit is inferred from each ingredient on its own rather than demonstrated together.
gaba + l-theanine
GABA and L-theanine are often combined in sleep supplements, and the pair may help you fall asleep a little faster and rest more soundly than either alone. The evidence is modest: an animal study and one small uncontrolled human study suggest a benefit, but no controlled human trial has confirmed a true synergy. Both compounds can add to the effects of alcohol and sedatives, so review the combination with your doctor or pharmacist if you take sleep, anxiety, or blood-pressure medication.
metoprolol + melatonin
Metoprolol blocks the beta-1 adrenergic receptors the pineal gland uses to receive its nighttime signal to make melatonin, so it tends to suppress your own melatonin and can contribute to insomnia and vivid dreams. A randomized trial in beta-blocker-treated patients found that low-dose bedtime melatonin improved sleep without interfering with metoprolol's cardiovascular benefits. This is a beneficial, low-concern combination rather than a harmful clash.
melatonin + magnesium
Melatonin provides a circadian timing signal while magnesium supports a calmer nervous system, so the two target different parts of the sleep problem and are commonly combined. The pairing is generally well tolerated short term, though rigorous proof of a specific two-ingredient synergy is limited.
passionflower + lemon balm
Passionflower (Passiflora incarnata) and lemon balm (Melissa officinalis) are both traditional calming herbs that act on the brain's GABA system - the main "slow down" signalling network. In laboratory studies, passionflower flavonoids appear to make GABA-A receptors more responsive, while lemon balm compounds appear to slow the breakdown of GABA. Because both lean in the same calming direction, taking them together is plausibly additive. There is, however, no human trial of this specific two-herb pair, so any combined benefit is theoretical and likely mild. The practical point is the shared sedative tendency: combining them with each other, or with other sedatives, can add up.
alcohol + mirtazapine
Mirtazapine and alcohol both depress the central nervous system, producing additive sedation, drowsiness, and impaired coordination and judgment. Mirtazapine's strong H1-antihistamine activity makes the sedative interaction with alcohol particularly pronounced, and the FDA label specifically advises avoiding alcohol during treatment.
valerian tea + benzodiazepines
Valerian (Valeriana officinalis) appears to act on the same GABA-A receptor system as benzodiazepines, so taking the two together may add to the sedative effect. The human evidence is largely theoretical and case-level, but the plausible result is extra drowsiness, slower reaction time, and more next-day grogginess.
l-theanine + magnesium
L-theanine and magnesium are both gentle, non-sedating relaxants that act on the same nervous-system pathways from different angles: L-theanine raises alpha-wave activity and modestly increases GABA, serotonin and dopamine, while magnesium dampens NMDA-receptor excitation and supports GABA-A signalling. A single preclinical study (Dasdelen et al., Frontiers in Nutrition, 2022) found a magnesium-L-theanine complex outperformed L-theanine alone in rats, but no human trial has tested the combination, so the pairing is reasonable rather than proven synergistic in people.
magnesium + glycine
Magnesium and glycine are commonly combined as magnesium bisglycinate, a chelate whose clearest benefit is being gentle on the gut and improving adherence, rather than dramatically higher absorption.