California Poppy

What Is California Poppy?

California poppy is a golden-orange wildflower of western North America whose flowering aerial parts are used as a mild sedative and calming herb. It is the state flower of California ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

It grows wild in grassland, open ground and desert from Washington south to Baja California, Sonora and Texas, and is planted as an ornamental across much of the world ^{14,15Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →Reference 15GBIF Secretariat (n.d.)Eschscholzia californica ChamView study →}. Native Americans used it to bring sleep to children, for toothache and to treat lice ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The aerial parts carry isoquinoline alkaloids, chiefly californidine and eschscholtzine, along with (S)-reticuline ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}. Research has looked at its calming, sleep-promoting and pain-relieving effects, mostly in mice; the one published randomised trial tested it inside a combination with hawthorn and magnesium ^{3,4,5Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →Reference 4Rolland A et al. · 1991Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic propertiesView study →Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}.

California poppy belongs to the same family as the opium poppy, Papaver somniferum, but to a different genus, Eschscholzia ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

How Is California Poppy Used?

California poppy is taken for anxiety, restless sleep and pain. The whole flowering aerial part is used.

• Tea — an infusion of the dried aerial parts.
• Tincture or liquid extract — a 1:5 tincture or a 1:2 liquid extract.
• Capsules — dried herb; a Swiss product recommendation is two 300 mg capsules before sleep ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}.
• Combination products — in Europe it is often sold in fixed combinations, with hawthorn and magnesium for anxiety, or with melatonin, passionflower and lemon balm for sleep ^{3,9Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →Reference 9Lemoine P et al. · 2019A combination of melatonin, vitamin B6 and medicinal plants in the treatment of mild-to-moderate insomnia: a prospective pilot studyView study →}.

Traditional Uses

Western Herbal Medicine

The whole aerial part (leaf, stem and flower) is gathered in bloom and taken as an infusion, a 1:5 tincture or a 1:2 liquid extract.

Western practice uses California poppy as a mild nervine with three overlapping actions: sedative, anxiolytic and analgesic. It is given for restless sleep, for anxiety and nervous tension, and for pain, often pain that keeps someone awake.

In Europe it is mostly dispensed in fixed combinations, with hawthorn and magnesium for anxiety, or with melatonin and other calming herbs for sleep ^{3,9Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →Reference 9Lemoine P et al. · 2019A combination of melatonin, vitamin B6 and medicinal plants in the treatment of mild-to-moderate insomnia: a prospective pilot studyView study →}.

Native American Medicine

California poppy is a traditional medicinal plant of Native Californians, and was used by the rural population of California for pain and as a sedative ^{4Reference 4Rolland A et al. · 1991Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic propertiesView study →}.

Recorded Native American uses include inducing sleep in children, treating lice, toothache and consumption, and use as an emetic and as a poison ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

Indications

• Anxiety and nervous tension [aerial parts; Western herbal medicine] ⚠Caution: The only published randomised trial gave California poppy together with hawthorn and magnesium, so its own contribution is unknown ³.
• Restless sleep and insomnia [aerial parts; Western herbal medicine] ⚠Caution: The published human sleep data come from multi-ingredient products ⁹. A placebo-controlled trial of the herb alone (NCT06795776) has finished but has not posted results.
• Pain, including pain that disturbs sleep [aerial parts; Western herbal medicine]
• Sleeplessness in children [plant; Native American use]
• Toothache [plant; Native American use]
• Head lice [plant; Native American use]

Botany

California poppy is an annual or perennial herb in the poppy family, Papaveraceae. It grows erect or spreading, 5–60 cm tall, and is smooth and sometimes bluish-green. Perennial plants form a heavy taproot ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The leaves grow at the base and along the stems. Each is deeply divided, one to four times over, into narrow lobes ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The flower bud is covered by a pointed cap formed from the two joined sepals, which falls off as the flower opens. The four petals are yellow to orange, 20–60 mm long, usually with an orange spot at the base, and have a satin sheen ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

Beneath the flower, the stem widens into a cup with a spreading rim. This rim is the feature that separates California poppy from the other Eschscholzia species ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The fruit is a slender capsule 3–9 cm long that splits from the base, often explosively. The seeds are brown to black, round and about 1.5–1.8 mm across ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The species is highly variable, and more than 90 varieties and forms have been described. Flora of North America recognises two subspecies: subspecies californica, usually perennial, and subspecies mexicana, an annual of the southwestern deserts ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}. Many colour forms are grown in gardens ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

The genus Eschscholzia has 12 species, native to western North America and northwestern Mexico ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

Distribution

California poppy is native to the western United States and northwestern Mexico ^{14,15Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →Reference 15GBIF Secretariat (n.d.)Eschscholzia californica ChamView study →}. Subspecies californica grows in grassy, open areas up to 2,000 m in California, Nevada, Oregon, Washington and Baja California. Subspecies mexicana grows in deserts up to 2,000 m in Arizona, California, New Mexico, Nevada, Texas, Utah and Sonora ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}. It flowers from late winter to late summer ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}.

It is widely planted in North America and elsewhere as an ornamental, roadside and reclamation plant. It often escapes from planting in North America but usually does not persist ^{14Reference 14ClarkClark, C. (n.d.). Eschscholzia californica Chamisso — species description, subspecies, habitat, distribution and recorded Native American uses — flora. In Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, Vol. 3. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004967View study →}. It has become naturalised in parts of Europe, South America (including central Chile and Argentina), southern Africa, Australia and New Zealand ^{15Reference 15GBIF Secretariat (n.d.)Eschscholzia californica ChamView study →}.

Growing Conditions

Cultivation snapshot for California Poppy

Lifetender-perennialZoneUSDA 6–10

• Full sun; medium water, low maintenance; readily self-seeds. Roughly USDA zone 6-10 (short-lived perennial in zones 8-10, annual in colder climates).

Grow it yourself

Farm Wiki is our cultivation-focused sister site, also run by Justin Cooke.

How to growComing soon

Find seedsComing soon

Pharmacology & Research

Research on California poppy is mostly preclinical: mouse behavioural studies from the 1990s and 2000s, and receptor and enzyme assays in cells. In mice, the extract calms, promotes sleep and eases anxiety, and a benzodiazepine-site blocker, flumazenil, removes those effects ^{4,5Reference 4Rolland A et al. · 1991Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic propertiesView study →Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}.

In the laboratory, the alkaloid (S)-reticuline enhances GABA-A receptor activity, and N-methyllaurotetanine binds serotonin 5-HT1A receptors ^{1,2Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →Reference 2Gafner S et al. · 2006In vitroAlkaloids from Eschscholzia californica and their capacity to inhibit binding of [3H]8-OH-DPAT to 5-HT1A receptors in vitroView study →}.

The one published randomised trial tested California poppy in a fixed combination with hawthorn and magnesium ^{3Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →}. A placebo-controlled Phase 3 trial of California poppy tablets for sleep (NCT06795776, n=104) has completed but has not posted results.

1. Anxiolytic

In mice, an aqueous extract produced an anticonflict effect at a low dose (25 mg/kg): the mice climbed more steps in the staircase test and spent more time in the lit compartment of a light/dark box. Sedation appeared only at doses above 100 mg/kg ^{4Reference 4Rolland A et al. · 1991Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic propertiesView study →}.

A follow-up study with an aqueous-alcohol extract found that flumazenil, which blocks the benzodiazepine site of the GABA-A receptor, suppressed both the anxiolytic and the sedative effects ^{5Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}.

The aerial-part alkaloid (S)-reticuline acts as a positive allosteric modulator at the α3, α5 and α6 GABA-A receptor subtypes. N-methyllaurotetanine had no effect on the α1β2γ2 receptor below 30 µM ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}, but binds the 5-HT1A receptor with a Ki of 85 nM ^{2Reference 2Gafner S et al. · 2006In vitroAlkaloids from Eschscholzia californica and their capacity to inhibit binding of [3H]8-OH-DPAT to 5-HT1A receptors in vitroView study →}.

The only randomised controlled trial (n=264, 3 months) tested a fixed combination of California poppy, hawthorn (Crataegus) and magnesium (Sympathyl) against placebo in mild-to-moderate generalised anxiety. It found a modest but significant advantage on the Hamilton anxiety score (−10.6 vs −8.9; p=0.005) ^{3Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →}.

Gap: no published trial has tested California poppy alone for anxiety, so its share of the combination’s effect, and an effective single-herb dose, are unknown.

2. Sedative / Sleep Support

In mice, the aqueous extract induced sleep and reduced activity at doses above 100 mg/kg ^{4Reference 4Rolland A et al. · 1991Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic propertiesView study →}.

In humans, a placebo-controlled screen of eight plant extracts, California poppy among them, used quantitative EEG in two crossover studies of 12 women each. Some extracts raised theta-band power and self-rated tiredness, in a pattern different from the diazepam reference ^{6Reference 6Schulz H et al. · 1998The quantitative EEG as a screening instrument to identify sedative effects of single doses of plant extracts in comparison with diazepamView study →}.

The only human sleep-outcome data come from an open-label, single-arm pilot study in 40 people with mild-to-moderate insomnia. They took a capsule combining melatonin, vitamin B6, California poppy, passionflower and lemon balm for two weeks, and sleep-quality scores rose from 5.4 to 7.3 out of 10 ^{9Reference 9Lemoine P et al. · 2019A combination of melatonin, vitamin B6 and medicinal plants in the treatment of mild-to-moderate insomnia: a prospective pilot studyView study →}. With several active ingredients and no control group, the result cannot be attributed to the poppy.

Gap: every published human sleep result is confounded by melatonin or other sedative herbs. A single-herb, placebo-controlled Phase 3 sleep trial has completed (NCT06795776, n=104) but has not posted results, and no hypnotic dose is defined.

3. Analgesic

In mice, an aqueous-alcohol extract produced peripheral analgesic effects. It did not relax muscles, did not protect against pentylenetetrazol convulsions, and showed no antidepressant, neuroleptic or antihistamine effects ^{5Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}.

The study did not establish how the analgesia works.

Gap: no human analgesia trial exists.

4. Antioxidant

A 2025 LC–MS study characterised four extracts of the aerial parts (ethyl acetate, ethanol, 70% ethanol/water and water), identifying 70 compounds, including rutin, quercetin glycosides and caffeic acid derivatives. The extracts showed antioxidant activity across standard assays ^{12Reference 12Kalyniukova A et al. · 2025Comprehensive metabolomic profiling and biological activity analysis of Eschscholzia californica extracts using LC-ESI-QTOF-MSView study →}.

There is no animal or human data.

5. Cholinesterase Inhibition

The same 2025 study screened the extracts for enzyme inhibition. The ethanol extract was the most active against acetylcholinesterase (2.39 mg GALAE/g) and the ethyl acetate extract against butyrylcholinesterase ^{12Reference 12Kalyniukova A et al. · 2025Comprehensive metabolomic profiling and biological activity analysis of Eschscholzia californica extracts using LC-ESI-QTOF-MSView study →}.

Computer docking in the same paper suggested that protopine, rutin, eschscholtzidine, boldine and (S)-scoulerine may bind dopamine D4 and D5 receptors and the serotonin transporter ^{12Reference 12Kalyniukova A et al. · 2025Comprehensive metabolomic profiling and biological activity analysis of Eschscholzia californica extracts using LC-ESI-QTOF-MSView study →}.

It is a single in vitro and in silico paper, with no behavioural or clinical follow-up.

6. Hypocholesterolemic

In a liver-cell model, the isolated alkaloid californidine raised LDL-receptor levels about as much as low-dose simvastatin (2.5 µM) and lowered PCSK9, as berberine did. Both reduced total cholesterol in the cells ^{13Reference 13Maharjan B et al. · 2022Evaluation of natural isoquinoline alkaloids on LDLR and PCSK9 in hepatocytes as potential hypocholesterolemic agentsView study →}.

The whole herb has never been tested for effects on blood lipids.

Gap: nothing shows that californidine reaches working concentrations in the body from a normal dose of the herb.

Mechanisms

(S)-Reticuline, a benzylisoquinoline alkaloid of the aerial parts, has been studied as a positive allosteric modulator of GABA-A receptors, and flumazenil blocks the extract’s sedative and anxiolytic effects in mice ^{1,5Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}. The aporphine N-methyllaurotetanine binds serotonin 5-HT1A receptors ^{2Reference 2Gafner S et al. · 2006In vitroAlkaloids from Eschscholzia californica and their capacity to inhibit binding of [3H]8-OH-DPAT to 5-HT1A receptors in vitroView study →}.

The ethanol extract and its alkaloids inhibit several drug-metabolising CYP enzymes in vitro. The tea and its main alkaloid, californidine, do not ^{8Reference 8Manda VK et al. · 2016Modulation of CYPs, P-gp, and PXR by Eschscholzia californica and its alkaloidsView study →}.

Clinical Trials

A single-herb Phase 3 placebo-controlled trial of California poppy tablets in adults with insomnia symptoms has completed (NCT06795776, n=104) without posted results. The only published controlled human evidence is a combination-product RCT (California poppy, hawthorn and magnesium) ^{3Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →}.

Two further completed trials tested multi-ingredient supplements containing the herb: a sleep supplement (POWEROFF, NCT03364101) and a tinnitus product (Audistim, NCT05300594). A single-herb sleep trial in chronic pain (CALPXT96, NCT02232256) was withdrawn before enrolment.

Last checked: September 2026.

Phytochemistry

The aerial parts carry isoquinoline alkaloids. The pavine alkaloids californidine and eschscholtzine are the two most abundant, and the aporphine N-methyllaurotetanine occurs at a level comparable to eschscholtzine ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}. The benzylisoquinoline (S)-reticuline is present at more than 1 mg/g of dry weight ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}.

The protopine alkaloids protopine and allocryptopine are much lower, at 0.01–0.5 mg/g, and reported protopine levels vary a hundredfold between analyses ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}. The benzophenanthridines sanguinarine and chelerythrine are also present ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}. An earlier isolation study added caryachine, O-methylcaryachine and a new pavine alkaloid ^{2Reference 2Gafner S et al. · 2006In vitroAlkaloids from Eschscholzia californica and their capacity to inhibit binding of [3H]8-OH-DPAT to 5-HT1A receptors in vitroView study →}.

Whether California poppy contains any morphine is not settled. A 2025 mass-spectrometry screen of the aerial parts listed compounds it identified as morphine derivatives and a codeine-related compound, but did not report how much of them was present ^{16Reference 16Kalyniukova A et al. · 2025In vitroComprehensive metabolomic profiling and biological activity analysis of Eschscholzia californica extracts using LC-ESI-QTOF-MS — phytochemical screen and in vitroView study →}. The plant’s main benzylisoquinoline, (S)-reticuline, is the starting point for morphine in the opium poppy, and one research group has suggested the body may convert it to morphine, as has been reported in rodents ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →}.

In eight commercial products, californidine ranged from 0.13 to 2.55 mg/g, eschscholtzine from 0.05 to 0.63 mg/g and protopine from 0.008 to 0.200 mg/g ^{11Reference 11Chauveau A et al. · 2023Alkaloids in commercial preparations of California poppy — quantification, intestinal permeability and microbiota interactionsView study →}.

A 2025 LC–MS study identified 70 compounds in extracts of the aerial parts. Besides alkaloids, including (S)-scoulerine, they include the flavonoids rutin, quercetin and kaempferol glycosides, and caffeic acid derivatives ^{12Reference 12Kalyniukova A et al. · 2025Comprehensive metabolomic profiling and biological activity analysis of Eschscholzia californica extracts using LC-ESI-QTOF-MSView study →}.

Alkaloid content varies widely between plants, extraction methods and commercial products ^{1,11Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →Reference 11Chauveau A et al. · 2023Alkaloids in commercial preparations of California poppy — quantification, intestinal permeability and microbiota interactionsView study →}.

Constituent Summary

Amounts are mg per g of dried aerial parts ^{1Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →} or of commercial product ^{11Reference 11Chauveau A et al. · 2023Alkaloids in commercial preparations of California poppy — quantification, intestinal permeability and microbiota interactionsView study →}.

Dosage

In human research California poppy has only been given inside fixed combination products, so no single-herb dose has been tested. The table lists the doses each study used.

Traditional Dosage

Western herbal practice uses the whole aerial parts as a tea or tincture.

Safety & Pregnancy

California poppy is generally well tolerated at traditional doses. Its main cautions are drug interactions with the alcohol tincture and added drowsiness with other sedatives.

Full Safety Detail

Tolerability. California poppy is generally well tolerated at traditional doses. In the three-month combination trial, adverse events were mainly mild or moderate digestive or psychological complaints, at a rate similar to placebo ^{3Reference 3Hanus M et al. · 2004RCTDouble-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxietyView study →}.

Drug-metabolising enzymes. In vitro, the ethanol extract and its alkaloids eschscholtzine and allocryptopine inhibited CYP3A4, CYP2C9 and CYP2C19, and protopine and allocryptopine inhibited CYP2D6. The extract and most of the alkaloids also activated the pregnane X receptor ^{8Reference 8Manda VK et al. · 2016Modulation of CYPs, P-gp, and PXR by Eschscholzia californica and its alkaloidsView study →}. The tincture may therefore interact with medicines cleared by these enzymes. The aqueous tea and its main alkaloid, californidine, had no effect on these enzymes ^{8Reference 8Manda VK et al. · 2016Modulation of CYPs, P-gp, and PXR by Eschscholzia californica and its alkaloidsView study →}. There are no clinical interaction studies.

Sedatives and alcohol. Because the extract’s calming effect works through the benzodiazepine site of the GABA-A receptor in mice, it may add to the effect of alcohol, benzodiazepines and other sedatives ^{1,5Reference 1Fedurco M et al. · 2015Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptorsView study →Reference 5Rolland A et al. · 2001Neurophysiological effects of an extract of Eschscholzia californica ChamView study →}.

References

1. Fedurco M, Gregorová J, Šebrlová K, et al. Modulatory effects of Eschscholzia californica alkaloids on recombinant GABAA receptors. Biochemistry Research International. 2015;2015:617620. https://pubmed.ncbi.nlm.nih.gov/26509084/
2. Gafner S, Dietz BM, McPhail KL, et al. Alkaloids from Eschscholzia californica and their capacity to inhibit binding of [3H]8-OH-DPAT to 5-HT1A receptors in vitro. Journal of Natural Products. 2006;69(3):432–435. https://pubmed.ncbi.nlm.nih.gov/16562853/
3. Hanus M, Lafon J, Mathieu M. Double-blind, randomised, placebo-controlled study of a fixed combination of Crataegus oxyacantha and Eschscholtzia californica and magnesium in mild-to-moderate anxiety. Current Medical Research and Opinion. 2004;20(1):63–71. https://pubmed.ncbi.nlm.nih.gov/14741074/
4. Rolland A, Fleurentin J, Lanhers MC, et al. Behavioural effects of the American traditional plant Eschscholzia californica: sedative and anxiolytic properties. Planta Medica. 1991;57(3):212–216. https://pubmed.ncbi.nlm.nih.gov/1680240/
5. Rolland A, Fleurentin J, Lanhers MC, et al. Neurophysiological effects of an extract of Eschscholzia californica Cham. (Papaveraceae). Phytotherapy Research. 2001;15(5):377–381. https://pubmed.ncbi.nlm.nih.gov/11507727/
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