We've covered various aspects of anxiety in detail starting with our summary of anxiety pathways here.
Let's dig deeper into a result of anxiety which can be overwhelming while in the throes of it.
Nausea from anxiety.
The other physiological effects of anxiety (quickened heart rate, raised blood pressure, etc) can be unsettling but nausea is downright debilitating.
Luckily, we're finally getting some good research on what drives it and more importantly...
What CBD can do for anxiety nausea specifically (besides just reducing anxiety itself).
We'll also touch base on why nausea can also be a side effect on the wrong kind of CBD.
By the way, that kind makes up 90% of the market!
The biggest brands out there need to do their research.
We'll dive deep into that research below.
Let's cover these topics:
- What covers nausea in the body and brain
- How does anxiety cause nausea
- The endocannabinoid system and anxiety nausea
- Can CBD help with anxiety nausea
- How much CBD to take for anxiety nausea
- What's the best kind of CBD for anxiety nausea
Let's get started
What covers nausea in the body and brain
There are many drivers of nausea in the body.
The most common:
- Parasite, bacteria, or bad substance is ingested
- Motion sickness and visual cues
- Intense pain
- Medications (especially chemo agents)
Think of nausea as a warning signal to the body/brain not to eat.
See our article on CBD and the gut.
It can precede vomiting or exists separately.
Either way, the signal is clear.
The areas of the brain tied to nausea are intricate and complicated.
Vomiting is actually a simpler process and the roots are better understood.
There is some overlap:
The triggering of nausea and vomiting is handled by a special center in the brain – the area postrema of the dorsal vagal complex (DVC).
The area postrema is interesting.
It's a way-station between our brain and our gut sitting at the end of the vagal nerve - the so-call gut-brain axis.
It can pick up signals from toxins in the digestive tract since it's not protected behind the blood-brain barrier.
When this area is impaired, subjects are unable to vomit most of the time:
Lesions of the AP prevent vomiting in response to most, but not all, emetic drugs.
Let's explain emetic while we're at it...it's something that causes nausea and vomiting.
It's not the only brain area, however.
Another "hub" area appears to be the solitary tract nucleus.
Nausea is most likely induced via stimulation of the area postrema via its connection to the NTS, which may serve as the beginning of the pathway triggering vomiting in response to various emetic inputs
In actuality, the areas tied to nausea seem to be as varied as the causes of nausea.
For example, the insular cortex figures strongly for nausea by itself.
It's also tied to pain pathways which explains why intense pain and nausea can go hand and hand:
Many of these areas involved in the nausea circuit specifically anterior cingulate cortex, insular cortex, nucleus accumbens, and amygdala are known to be involved in the processing of acute as well as chronic painful stimulus
Many brain areas can be involved in the nausea response but they have one thing in common.
These are ancient parts of our brain - the old reptilian "brain".
It's in charge of basic autonomic (think automatic) processes in the body.
You know...breathing, heartbeats, fight or flight.
Multiple pathways as shown by the different ways that anti-nausea medications work.
To make things more complicated, there are individual differences:
Inherent factors that are described are age, gender, and race; psychological factors that are included are anxiety, expectation, anticipation, and adaptation.
We can look at how anti-nausea medications work to tease out the pathways involved.
Some key pathways affected by anti-nausea medications that we can actually affect are:
- Serotonin 5ht3 receptors specifically
Chemicals that block these, so-called "antagonists" are known to have anti-anxiety effects.
We'll come back to these later.
The gut connection to nausea (get bad things out) is easy to understand. But what about anxiety?
Let's go back to that reptilian brain.
How does anxiety cause nausea
We all know the psychological effects of anxiety.
What about the physiological effects of our body?
Think of anxiety as an unresolved or prolonged state of fight or flight.
Discount fight or flight.
Sometimes, full-blown (that's a panic attack).
See our article on CBD and panic attacks.
There are immediate physical effects on this state.
As Harvard medical puts it:
As neurotransmitters carry the impulse to the sympathetic nervous system, heart and breathing rates increase, muscles tense, and blood flow is diverted from the abdominal organs to the brain.
The sympathetic nervous system is our fight or flight system.
Did you catch that last part.." diverted from the abdominal organs to the brain".
It's the old "fight or flight" versus "rest and digest".
"Sympathetic" equals fight or flight.
The body is on high alert but as Harvard medical states:
But its physical effects can be counterproductive, causing light-headedness, nausea, diarrhea, and frequent urination
Sound like symptoms from something else we know?
Autonomic imbalance and in particular decreased parasympathetic tone is implicated in anxiety, depression, post-traumatic stress disorder, and schizophrenia
Parasympathetic is the counterbalance (rest and digest) to our fight or flight system.
What's really fascinating is new research on the endocannabinoid system.
Let's go there now before we look at CBD for anxiety nausea.
The endocannabinoid system and anxiety nausea
The endocannabinoid system is shared by every animal on the planet.
It goes back about 600 million years ago which means that evolution stumbled on something very useful.
It's used to balance other key systems from applied "stress":
- Nervous system - including neurotransmitters like serotonin
- Endocrine system - including hormones like vasopressin and histamine
- Immune system - a key system responding to invaders with nausea and vomiting
It turns out that this system is key to governing the nausea response!
Of course, the first clues came from animal studies such as this one:
In a rat model of nausea, when levels of endocannabinoid were increased systematically by the administration of a FAAH inhibitor, nausea was reduced
Let's introduce some players (which will come up later).
FAAH is naturally occurring endocannabinoid which breaks down another one called Anandamide.
Reduced FAAH led to reduced nausea.
By the way, the same relationship exists for both anxiety and pain!
See the article on the woman who can't feel pain and anxiety here.
Remember that the insular cortex area of the brain more associated with the "feeling" of nausea versus vomiting?
Activation of the ECS in the insular cortex can regulate the expression of nausea in animals; interestingly, it appears that 2-AG, rather than anandamide, mediates this regulatory control system
ECS is short for the endocannabinoid system.
2-AG is the most prominent endocannabinoid in our brain.
By the way, that article is an interesting read on all the ways the endocannabinoid system interacts with the gut including pain, motility, and more.
Another key avenue is the serotonin pathway...specifically 5ht3 receptors.
When the receptor is activated to open the ion channel by agonists, the following effects are observed:
CNS: nausea and vomiting center in brain stem, anxiety, seizure propensity, pro-nociception
PNS: neuronal excitation (in autonomic, nociceptive neurons), emesis
CNS is the central nervous system. PNS is the peripheral nervous system.
Did you catch the overlap there?
Anxiety and nausea both share this pathway.
There's some interesting research on how nausea may have jumped its original role to keep us from eating.
It's tied to so many brain areas that there can be some wire-crossing.
Anxiety may be an example of this false trigger for nausea.
That insular cortex is also tied to perceiving a lack of "well-being" in the system.
Then there's the 5ht3 serotonin pathway.
Animal studies pointed the way:
These results confirm that LiCl-induced nausea is triggered by elevated 5-HT release in the IIC and is attenuated by treatments that reduce 5-HT availability in this region.
We have everything right there.
- 5ht3 stimulation (Serotonin)
- IIC - short for the insular cortex
See our article on a complete guide to CBD and serotonin.
Okay...let's finally get to CBD.
Can CBD help with anxiety nausea
We've covered the pathways for CBD and anxiety here.
Let's focus on anxiety nausea specifically.
First, the fight or flight response (our trigger from anxiety).
The study on CBD and public speaking anxiety is a great litmus test.
They actually looked at the physiological signs of anxiety after CBD.
Following the same rationale as above, it is well-known that more pronounced bodily symptoms may contribute to the clinical diagnosis of SAD, and this result suggests that CBD also protects the patients from their subjective physiological abnormalities induced by the SPST.
SAD is a social anxiety disorder.
Basically, CBD brought down the sympathetic or autonomic responses from fear of public speaking in people with a social anxiety disorder!
They measured heart rate, blood pressure, and skin conductance levels.
All key responders in our fight or flight response.
That's a good start to reducing the physical effects of anxiety.
- CBD and cortisol (our main stress hormone)
- CBD and CRF (a hormone that starts the fight or flight response,
- CBD and stress for anxiety
Let's look at nausea specifically.
CBD appears to reduce anxiety on two different serotonin pathways:
Let's look at each.
Cannabidiol, a non-psychotropic component of cannabis, attenuates vomiting and nausea-like behavior via indirect agonism of 5-HT(1A) somatodendritic autoreceptors in the dorsal raphe nucleus.
Remember how we said there were multiple brain areas tied to nausea?
The type of serotonin receptors (1 or 3) and the brain area can have different impacts.
Remember how chemicals that block 5ht3 reduced anxiety?
What about CBD there?:
They further suggest that allosteric inhibition of 5-HT3 receptors by CBD may contribute to its physiological roles in the modulation of nociception and emesis.
Emesis - Vomiting.
Remember that blocking 5ht3 also reduced anxiety! (cross-wiring).
Then there's the whole motion sickness nausea effect.
An interesting study found that people who suffered from motion sickness nausea had significantly lower levels of Anandamide then those that did not suffer.
Moreover, the simulated flight caused anandamide levels to drop further!
They're final assessment:
These findings demonstrate that stress and motion sickness in humans are associated with impaired endocannabinoid activity
Anandamide...our "bliss" hormone.
What does CBD do for anandamide levels?:
CBD prevented increased anxiety produced by chronic unpredictable stress, in addition to increasing hippocampal AEA; these anxiolytic effects depended upon CB1R activation and hippocampal neurogenesis, as demonstrated by genetic ablation techniques
AEA is anandamide.
There are many effects from increasing anandamide (such as reducing psychotic behavior in schizophrenia) but we chose a study on anxiety specifically.
Check out CBD and long term anxiety to learn why that hippocampal neurogenesis is so important and CBD and schizophrenia.
Finally, CBD's effect on histamine.
The histamine H1 receptor is key pathways for blocking nausea.
Just look at the "knock-on" effects of antihistamine medications:
First-generation antihistamines have several indications that primarily include nausea and vomiting secondary to motion sickness and vertigo,
This makes sense as the role of histamine is to get bad things out of body fast!
Don't go so fast, Anandamide!:
Also, AEA has been shown to inhibit mast cell degranulation in a human mast cell line Mast cell degranulation is the process of "releasing" histamines.
Check out CBD for histamine and anxiety here.
On to more practical questions.
How much CBD to take for anxiety nausea
We don't have exact information from research on this.
More importantly, for anxiety nausea, everyone has a different threshold.
The best approach is the standard one.
Test about 25-30 mg of CBD (placed under the tongue for up to 60 seconds) first and test how you feel.
Feedback points to about 40-80 mg but studies do show dose-dependent responses up to 300 mg.
One study looked at the long term effect (neurogenesis) of CBD and found 300 mg was the max for that effect.
It started to go down from 300 to 600 mg in their study although the initial antianxiety effect continued.
Let's look at the best type of CBD.
What's the best kind of CBD for anxiety nausea
Two important considerations come up.
- Clean CBD by itself
- Histamine responses
Keep in mind that all the research above is based on CBD by itself...so-called CBD Isolate.
See our article on full-spectrum CBD versus CBD isolate for anxiety.
Most of the market is pushing full-spectrum CBD.
This is one reason people say they actually get nausea as a side effect from CBD.
It's a histamine response to all that plant material (and maybe even up to .3% THC).
Roughly 40-60% of the population has histamine issues.
This number goes higher for women and as we get older.
Keep in mind that an entire class of anti-nausea medications actually work by blocking histamine release!
We don't want to go the other way with lots of plant material.
It's the key reason we started IndigoNaturals after going through bottles by some of the biggest brands on the market.
Let us know your ideal dosage for anxiety nausea and be well!
Master overview of CBD and anxiety pathways to look at various aspects we can directly affect.
Links to CBD and anxiety research with dozens of anxiety-specific topics.
Always work with a doctor or naturopath with any supplement!
The information provided here is not intended to treat an illness or substitute for professional medical advice, diagnosis, or treatment from a qualified healthcare provider.