CBD in Bipolar Disorder: Can Cannabinoids Affect Bipolar Affective Disorder?
The Science Behind Using CBD for Bipolar Affective Disorder
The National Institute of Mental Health estimates that 4.4% of US adults will be diagnosed with bipolar affective disorder (BPAD) in their lifetime. Adults with BPAD experience the highest degree of disability among psychiatric patients, with approximately 82.9% suffering from severe disability.
Bipolar affective disorder and its variants can be resistant to treatment, which may explain the high rate of disability. Preliminary studies suggest that cannabinoids have the potential to improve BPAD symptoms in some individuals by regulating the endocannabinoid system.
What is Bipolar Disorder?
Bipolar affective disorder is a mental illness that causes significant changes in mood, motivation, and energy. This cycling involves periods of euphoria (manic episodes) followed by periods of hopelessness (depressive episodes), a hallmark of the disease.
Preliminary research supports the use of CBD for treating bipolar affective disorder.
There are four types of bipolar affective disorder:
- Bipolar I disorder
- Bipolar II disorder
- Cyclothymic disorder
- Bipolar spectrum disorder
The severity and frequency of symptoms determine the type. Type I is the most severe.
Symptoms of Manic Episodes
Manic episodes are characterized by exaggerated self-esteem, insomnia, racing thoughts, slurred speech, inability to focus, and impulsive behavior. These episodes mainly affect those diagnosed with Bipolar I disorder. Hypomania, a less severe form, occurs in other BPAD variants.
Mania, despite being a “high” stage, can have catastrophic consequences, often leading to hospitalization, psychotic symptoms, or severe disability. Untreated manic episodes can turn into psychosis.
Symptoms of Depressive Episodes
Depressive episodes mimic major depressive disorder, including feelings of sadness, emptiness, hopelessness, and loss of interest in activities. Symptoms also include changes in sleep patterns, appetite, concentration problems, feelings of worthlessness or guilt, and suicidal thoughts or attempts.
This cycle represents the “low” point of bipolar disorder. The severity varies depending on the type of bipolar disorder. Patients with Bipolar I disorder may experience mixed episodes with signs of both mania and depression.
Conventional Treatments for Bipolar Disorder
Prescription medications and psychotherapy can relieve BPAD symptoms in most patients. However, treatment resistance is a significant concern, with up to 50% of individuals attempting suicide at least once in their lifetime.
Medications for BPAD include anticonvulsants, antimanic medications, and antidepressants. Antidepressants alone can lead to mania or severe cycling, hence mood stabilizers or anticonvulsants are often used to mitigate these effects.
Lithium is the only drug consistently shown to reduce suicide rates in bipolar patients. Recent research suggests that manipulating the endocannabinoid (EC) system may provide an alternative approach. These neurotransmitters bind to cannabinoid receptors and influence brain function.
Endocannabinoid System Dysfunction and Bipolar Affective Disorder
The endocannabinoid system, discovered in the mid-1990s, consists of CB1 and CB2 receptors. Cannabinoids, found both in the human body and in cannabis plants, interact with these receptors to alter brain function. Endocannabinoids are naturally produced neurotransmitters, while phytocannabinoids are found in cannabis plants.
Postmortem studies of brains from individuals with BPAD show abnormalities in the EC system. A study using brain slices from mice showed dysfunctional CB2 receptors that inhibit serotonin release, suggesting a healthy EC system helps regulate mood.
A study of endocannabinoid gene variants in patients with major depressive disorder, BPAD, and healthy controls found significant differences in the CB1 receptor (CNR1) and fatty acid amide hydrolase (FAAH) genes among those with BPAD and major depressive disorder.
Regulation of the Endocannabinoid System with Phytocannabinoids
Endocannabinoid receptors are distributed in brain areas associated with BPAD and other mental illnesses. Studies show that patients with abnormalities in the CNR1 gene are at higher risk of treatment resistance.
Phytocannabinoids may offer a way to manipulate the EC system and regulate brain chemicals traditionally targeted by pharmacological drugs. However, these studies are preliminary.
Anandamide and THC (Tetrahydrocannabinol)
Anandamide, known as the bliss molecule, is naturally produced in the body and structurally similar to THC. Both bind to CB1 receptors, affecting memory, concentration, movement, perception, and pleasure.
The FAAH genes activate anandamide; mutations in these genes can lead to deficient levels of anandamide. Supplementing with THC may help restore chemical balance and alleviate symptoms of BPAD.
Cannabidiol (CBD)
CBD has been shown to inhibit serotonin reuptake, potentially correcting CB1 receptor abnormalities. If CBD functions similarly in the human brain, it may offer an alternative to conventional antidepressants, especially for those with treatment-resistant BPAD.
A randomized clinical trial found that CBD reduced abnormal brain function in regions associated with psychosis, suggesting a therapeutic effect on manic symptoms. CBD might regulate both depressive and manic symptoms, providing an option for those who do not respond well to lithium.
Other Cannabinoids
Cannabis contains over 500 chemicals, including more than 100 cannabinoids. While research has primarily focused on CBD and THC, other cannabinoids like CBG and CBCV show potential for treating mood disorders. Further study is needed to isolate and understand the effects of these compounds.
Research supports further investigation into using CBD for bipolar affective disorder. While still in the early stages, it seems likely that CBD and other cannabinoids could help manage BPAD symptoms.
Using CBD and Other Cannabinoids for Bipolar Disorder
CBD has not been shown to cause significant side effects. Individuals experiencing BPAD symptoms or those previously diagnosed should consult a medical professional before starting or changing treatments. Even those with treatment-resistant BPAD can benefit from traditional methods, such as psychotherapy.
Regulating the endocannabinoid system with phytocannabinoids may provide relief for treatment-resistant BPAD patients. More human clinical trials are needed to confirm preliminary data, but the future of cannabinoids as a treatment for bipolar disorder looks promising.
Read more about CBD and depression here.