CBD Oil for Schizophrenia - April 2024

Why People Are Taking CBD for Schizophrenia

Traditional antipsychotics are the medications prescribed for schizophrenia cases.

According to a 2018 study, antipsychotic drugs may have adverse side effects, such as sexual dysfunction, sedation, weight gain, glycemic and lipid dysfunction, and extrapyramidal symptoms (EPS)⁽⁶⁾. These side effects are well-documented in the medical literature.

Even when these adverse symptoms disappear, schizophrenia still requires lifelong treatment⁽⁷⁾.

For these reasons, patients diagnosed with psychotic disorders, like schizophrenia, have started exploring unconventional treatments⁽⁸⁾.

These alternative remedies may include the use of the nonpsychoactive component of the Cannabis sativa plant, cannabidiol (CBD).

Extrapyramidal symptoms are disorders that may cause muscle control and movement problems throughout the body, commonly seen in the face⁽⁹⁾.

The first case study on CBD as an antipsychotic treatment for schizophrenia was done in 1995 by Zuardi AW and his colleagues. They gave a 19-year-old female with schizophrenia CBD for four weeks⁽¹⁰⁾.

The researchers observed that the test subject’s acute psychotic symptoms markedly improved.

In 2018, Philip McGuire and his co-authors conducted a randomized controlled trial on 88 patients with schizophrenia. The researchers, who aimed to compare CBD with placebo as an add-on treatment to the patients’ antipsychotics, gave CBD to 43 patients and placebo to 45 patients⁽¹¹⁾.

The authors observed that there were significant differences between those who were treated with CBD and placebo.

The CBD group exhibited lower levels of positive psychotic symptoms. They were more likely to be rated as improved and not severely unwell by treating clinicians. 

The researchers also discovered that CBD was well-tolerated by the test subjects.

There were adverse effects observed in the CBD and the placebo groups. Some patients who received CBD exhibited typical CBD side effects, such as nausea, vomiting, diarrhea, and abdominal pain. 

Meanwhile, some patients from the placebo group reported sleepiness and altered perception. 

The symptoms subsequently resolved in the CBD and placebo patients. 

In a randomized, double-blind, monotherapy trial of CBD compared with the antipsychotic drug amisulpride, researchers found that CBD treatment was associated with fewer extrapyramidal symptoms and less weight gain⁽¹²⁾.

In the study, 39 schizophrenia patients were tested. Of the 39, 19 were given CBD, while 20 were administered amisulpride – granted, amisulpride is not one of the most commonly prescribed schizophrenia drugs.

However, there have been studies suggesting that CBD alone might not be useful in treating schizophrenia. 

A very small randomized placebo-controlled clinical trial was conducted by Douglas Boggs and his colleagues on 36 patients with chronic schizophrenia⁽¹³⁾.

They gave 18 patients CBD, while the other 18 received a placebo. Research has found that CBD, compared with placebo, had no therapeutic effects on schizophrenia symptoms. 

A study was conducted on three patients who had treatment-resistant schizophrenia. In the study, the patients were initially given a placebo for five days⁽¹⁴⁾.

From the 6th to the 35th day, the patients were given CBD daily. On the 36th day, CBD treatment was stopped, and the researchers re-administered a placebo for five days. Then, the patients were given the antipsychotic drug olanzapine for over 15 days.

Only one patient showed mild improvement. Hence, the researchers concluded that CBD therapy alone might not have promising effects on treatment-resistant schizophrenia.

How CBD Oil Works to Alleviate Symptoms of Schizophrenia

CBD for Cognitive Function

According to the American Psychiatric Association (APA), individuals with schizophrenia may have impaired brain function. These symptoms include declining educational performance and problems with attention, memory, and concentration⁽¹⁵⁾.

A 2017 systematic review of 18 preclinical and nine clinical studies concluded that CBD might help improve cognitive performance in preclinical models of schizophrenia, Alzheimer’s disease, meningitis, sepsis, cerebral malaria, hepatic encephalopathy, and brain ischemia⁽¹⁶⁾. 

However, the researchers noted that, currently, there is a lack of human clinical trials investigating CBD’s effects on the cognitive impairment of schizophrenia patients. Therefore, they recommend further research on the topic.

CBD for Enhanced Anandamide Signaling

According to research, CBD treatment markedly increased anandamide levels in patients with schizophrenia. Higher levels of anandamide were associated with clinical improvement due to the purported reduction of psychotic symptoms⁽¹⁷⁾.

Anandamide is a transmitter of the endocannabinoid system (ECS) that helps in the regulation of pain, cognition, and mood.

The ECS is responsible for regulating body functions, such as mood, memory, pain perception, and appetite⁽¹⁸⁾. Activation of its cannabinoid receptors may have effects on these functions. 

Research conducted by F. Markus Leweke and co-authors also revealed that the ECS is closely linked to schizophrenia⁽¹⁹⁾. The researchers concluded that CBD was a promising antipsychotic treatment with a favorable side effect profile. 

CBD for Psychosis 

Schizophrenia is characterized by psychotic symptoms, including paranoid delusions, hallucinations, like hearing voices, and distorted or exaggerated perceptions and behaviors⁽²⁰⁾.

Research published in the JAMA Psychiatry revealed that CBD might attenuate psychotic symptoms by resetting the activity in brain areas linked to the beginning of psychosis. These brain regions include the striatum, midbrain, and the medial temporal cortex⁽²¹⁾

JAMA Psychiatry is the American Medical Association’s peer-reviewed medical journal.

In the study conducted by Bhattacharyya S and his co-authors from King’s College London, 33 participants with psychotic symptoms were given either 600mg of CBD or a placebo capsule.

The subjects were administered a single dose of CBD and placebo. Then, they were asked to accomplish a memory task. This test engaged the three brain areas linked to initial psychosis development.

While the participants were doing the tasks, their brains were scanned with an MRI scanner. 

The researchers observed that the brains of the participants who took CBD exhibited less severe abnormalities than those who were given a placebo.

Hence, the researchers concluded that CBD might have properties that could reset or modulate abnormal activity in the brain regions critical to psychosis.

Another study found in the Journal of Psychopharmacology stated that CBD might help alleviate psychotic symptoms. 

Six patients who had Parkinson’s disease were administered CBD in varying doses, up to 400mg daily⁽²²⁾.

In four weeks, the test subjects’ psychotic symptoms significantly improved.

In a 2019 research published in the Journal of Clinical Medicine, researchers reviewed human clinical studies on CBD’s effects on psychotic disorders and substance abuse, including cannabis use disorders. 

The researchers concluded that CBD might help in the symptoms of schizophrenia, especially in the early stages of the mental illness⁽²³⁾.

The authors also found that CBD mixed with tetrahydrocannabinol (THC) was promising in attenuating short-term withdrawal and cravings in cannabis users.

Like CBD, THC comes from the cannabis plant. However, unlike CBD, which does not get users high, THC is psychoactive.

Research in the journal Therapeutic Advances in Psychopharmacology revealed that CBD use might contribute to the significant improvement of symptoms of psychosis⁽²⁴⁾.

The study also outlined CBD’s promising effects in patients with non-schizophrenia spectrum disorder psychosis, like Parkinson’s disease. The study’s authors are Cathy Davies and Sagnik Bhattacharyya, Ph.D.

CBD for Anxiety

Research in 2016, published in the Industrial Psychiatry Journal, has found that anxiety disorder was significantly higher in patients diagnosed with schizophrenia⁽²⁵⁾.

A study in 2015 outlined CBD’s purported benefits in attenuating the symptoms of various anxiety disorders, such as generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, post-traumatic stress disorder, and social anxiety disorder⁽²⁶⁾.

The research reviewed several preclinical, clinical, human experimental, and epidemiological studies.

Another study that was published in The Permanente Journal stated that CBD might have properties that could be beneficial to anxiety-related disorders. 

The researchers also observed improvements in the test subjects’ sleep scores within the first month⁽²⁷⁾.

A study that was published in the Brazilian Journal of Psychiatry demonstrated that CBD might have anxiolytic (anxiety-reducing) properties that could help reduce an individual’s stress response to particular situations⁽²⁸⁾.

Guimarães FS and Crippa JA were among the authors of the said study.

In the study, 57 male volunteers were given varying doses of CBD (150mg, 300mg, and 600mg) or placebo. 

Only those who were administered 300mg of CBD exhibited reduced anxiety during the study’s public speaking test.

A 2014 review published in the journal CNS and Neurological Disorders – Drug Targets revealed that CBD might have anxiolytic and antidepressant effects on animal test subjects of several studies⁽²⁹⁾. 

Hence, researchers concluded that CBD might have promising effects on anxiety and depression.

CBD therapy alone may not be as effective in treating schizophrenia⁽³⁰⁾. However, it can be added to conventional antipsychotic medications⁽³¹⁾.

Unfortunately, these antipsychotics may have detrimental effects on patients, such as muscle spasms, pain, and nausea⁽³²⁾. 

CBD for Muscle Spasms 

A double-blind, randomized, placebo-controlled study found in the journal Neurological Research found that Sativex, a medical cannabis extract with CBD and THC, might have properties that could help alleviate muscle spasms in multiple sclerosis patients⁽³³⁾.

In the study, the use of cannabis-derived Sativex on the test subjects reduced their treatment-resistant spasticity (muscle stiffening or tightening).

Another study, conducted on 189 patients with multiple sclerosis and spasticity, found that Sativex drug administration was more effective in treating muscle spasms than placebo⁽³⁴⁾.

CBD for Pain

An animal study published in the European Journal of Pain has shown that topically-applied CBD might help alleviate pain and inflammation in rodent test subjects with arthritis⁽³⁵⁾.

A review of several preclinical and clinical studies concluded that CBD’s analgesic properties might help alleviate hard-to-treat chronic pain⁽³⁶⁾.

The researchers reminded consumers to take caution when purchasing CBD due to the prevalence of unregulated and potentially toxic CBD products.

CBD for Nausea

Research found in the British Journal of Pharmacology showed that CBD might have antiemetic (nausea-reducing) effects that might be beneficial to the treatment of nausea and vomiting induced by chemotherapy⁽³⁷⁾.

The Pros and Cons of CBD Oil for Schizophrenia

• Several studies on humans and animals have revealed CBD’s purported benefits on schizophrenia treatment. 

Research also found evidence of the antipsychotic effects of CBD, which might help treat schizophrenia symptoms, such as psychosis.

• Antipsychotic medications may have side effects, which may be detrimental to the health of schizophrenia patients. These effects include muscle spasms, pain, and nausea⁽³⁸⁾.

Meanwhile, studies show that CBD is well-tolerated by patients with schizophrenia. Compared with antipsychotics, CBD has fewer side effects, including nausea, diarrhea, and headaches⁽³⁹⁾.

• There are no recorded cases of CBD abuse in humans⁽⁴⁰⁾. Hence, schizophrenia patients developing an addiction for the substance is highly unlikely. 
• If CBD use in a state is permissible by law, prescriptions are not required when purchasing CBD products.

The Cons

• Further research needs to be conducted on CBD as a stand-alone therapy for schizophrenia and its symptoms, like psychotic episodes.
• Concerning legalization, only CBD for the treatment of epilepsy has been approved by the United States Food and Drug Administration (FDA). 

CBD use has not been approved for the treatment of mental disorders, such as schizophrenia.

• CBD and antipsychotics may have drug interactions. The enzymes cytochrome P450 are involved in the metabolism of antipsychotic medications⁽⁴¹⁾. CBD is an inhibitor of cytochrome P450⁽⁴²⁾. The drug interactions could be toxic to the patients.  

• CBD products are unregulated by the FDA. Researchers have found that some products do not contain the precise amounts of CBD and ingredients listed on their labels⁽⁴³⁾. 

How CBD Oil Compares to Alternative Treatments for Schizophrenia

Vitamins for Schizophrenia

According to a 2015 study found in the journal CNS Drugs, specific vitamins, such as folic acid, vitamin B12, and vitamin D, might help with schizophrenia⁽⁴⁴⁾.

Researchers observed that vitamin D might have protective effects useful for individuals who have a high risk of psychosis development.

CBD may have drug interactions with vitamins, such as folic acid⁽⁴⁵⁾. Thus, the use of CBD with these supplements is not advised.

Gluten-Free Diet for Schizophrenia

A study published in the journal Acta Psychiatrica Scandinavica has shown that a gluten-free diet has resulted in the full remission of schizophrenic symptoms in the human test subjects⁽⁴⁶⁾.

The researchers concluded that gluten withdrawal is a safe and economical alternative remedy for schizophrenia symptoms. 

However, they also noted that the drastic reduction of symptoms was exhibited only by a subset of patients with schizophrenia.

According to Harvard Medical School, a gluten-free diet helps eliminate inflammation⁽⁴⁷⁾.

Similarly, CBD has been suggested to help with inflammation. 

A 2019 review revealed that CBD has anti-inflammatory properties that might help with several conditions⁽⁴⁸⁾. 

Schizophrenia patients who want to use CBD to supplement their gluten-free diet should avoid using CBD products that contain gluten. They should always check the labels first.

How to Choose the Right CBD for Schizophrenia

The National Institute on Drug Abuse says that there may be a link between marijuana use and increased risk factors for psychiatric disorders, such as schizophrenia, anxiety, and depression⁽⁴⁹⁾. 

Whether it is recreational or medical marijuana, its primary ingredient is delta-9-tetrahydrocannabinol, also known as THC.

There are three CBD types: full-spectrum CBD, broad-spectrum CBD, and CBD isolates.

Among the three, only full-spectrum CBD contains THC. However, in compliance with federal laws, credible CBD manufacturers ensure that their full-spectrum CBD products contain 0.30% of THC at most. 

These full-spectrum CBD products, which have trace amounts of the psychoactive THC, also have terpenes, flavonoids, fatty acids, and essential oils.

It is suggested that all these active ingredients synergize and generate the maximum therapeutic benefits of the Cannabis sativa plant. This process is known as the entourage effect.

Despite its alleged benefits, full-spectrum CBD products should be used with caution, especially when the user has been diagnosed with schizophrenia. It is also essential to note that some drug tests may detect even small THC amounts in full-spectrum products. 

For a THC-free product containing all the other ingredients of a full-spectrum CBD oil, patients may purchase broad-spectrum CBD products.

Schizophrenia patients who want to use isolated cannabidiol may buy CBD isolates.

Here are some guidelines for CBD buyers before purchasing any CBD product:

1. Make sure that state laws permit CBD use.
2. Look for CBD products that are non-GMO and have been certified as organic and hemp-derived. 
3. Potential buyers from online stores should ensure the CBD manufacturer’s legitimacy and credibility. Reviews offer insights on the brand and its products. If the manufacturer has no brick-and-mortar store, buyers should double-check if the online CBD store has government authorization. 
4. Check the extraction process of the CBD product before making any purchase. According to a 2018 study, CO2 extraction is considered a safe method⁽⁵⁰⁾. During extraction, carrier oils are used so they can be infused with CBD and other essential phytocompounds. The most natural oils include medium-chain triglycerides (MCT) from coconut oil, hemp seed oil, and extra-virgin olive oil.
5. Buyers should also review reports, certificates, and analyses from third-party laboratories. Credible manufacturers allow customers to access these essential documents on their website. Some products have QR codes that can lead customers to a certain item’s certificate of analysis upon scanning.  
6. Before making any purchase, buyers should first seek the advice of a medical professional. 

CBD Dosage for Schizophrenia

There is no standard dosage for CBD in treating schizophrenia symptoms. Patients also have varying severity of their symptoms. Hence, no standard dosage of CBD oil can work for all schizophrenia patients.

Patients are advised to follow the dosage guidelines from the manufacturer of the CBD product purchased. They are also advised to start with small amounts of CBD. If no adverse effects are observed, the dosage may be increased gradually until the patient experiences relief.

Schizophrenia patients are also encouraged to first consult with their doctor before including CBD in their therapy.

How to Take CBD for Schizophrenia

There are various CBD formats and formulations available for schizophrenia patients.

CBD may be ingested as it comes in soft gel and capsule formats. CBD oil may also be mixed with food or beverages if the patient dislikes CBD’s grassy taste.

CBD oil may be therapeutic, especially when schizophrenia patients are experiencing anxiety-related symptoms. Some oils have soothing flavors, such as peppermint and menthol.

CBD also comes in tincture form (droppers) and may be administered sublingually (under the tongue) for around one minute before swallowing. This application is believed to be more effective.

Schizophrenia patients who may have developed complications, such as nicotine dependence, may switch to CBD vape pens instead. Aside from being a popular way of getting CBD into one’s system, CBD vaping allows individuals to ingest CBD instantly.

However, vaping may cause problems in some people⁽⁵¹⁾.

Vaping also makes it difficult for users to determine the amounts of CBD they have ingested with each draw. Results may be expected to last for 30 minutes to two hours maximum.

CBD topicals, like lotions, salves, creams, and balms, are also available. However, they may not be the appropriate format to use in treating schizophrenia symptoms.

Understanding Schizophrenia

Schizophrenia is a mental health disorder that may also overlap with other conditions, such as bipolar disorder⁽⁵²⁾.

It is a severe condition characterized by patients interpreting reality abnormally. Schizophrenia may lead to delusions, hallucinations, and severely disordered thinking and behaviors that could affect daily functioning and even be disabling to some individuals⁽⁵³⁾.

Schizophrenia Symptoms

Schizophrenia symptoms may be categorized into the following⁽⁵⁴⁾:

• Positive symptoms  – These include hallucinations, delusions, distorted perceptions, behaviors, and beliefs.
• Negative symptoms – These can be characterized by a decrease or loss of the ability to speak, create plans, find pleasure, or express emotions.
• Disorganization symptoms – these refer to the disordered speech and thinking in individuals, bizarre behaviors, or abnormal movements.
• Cognitive symptoms – These are the issues involving concentration, memory, attention, and decline in educational performance.

Schizophrenia Complications

Schizophrenia treatment is life-long. Patients diagnosed with the disorder should immediately have it treated as it can lead to several complications, such as⁽⁵⁵⁾:

• Anxiety and related disorders (obsessive-compulsive disorder)
• Substance use disorders (e.g., alcohol, drugs, and nicotine)
• Suicide (attempts and thoughts of the act)
• Social interaction problems
• Difficulty attending work or school
• Depression
• Financial problems (such as homelessness)
• Being victimized by others
• Other health and medical problems
• Aggression (not as common as other symptoms)

Conclusion

Schizophrenia is a mental disorder with debilitating effects on the life of patients.

Studies have found that CBD might be promising as a potential treatment for schizophrenia and its symptoms. 

Research has been done on CBD as monotherapy and adjunctive therapy to conventional treatments, such as antipsychotics and psychosocial sessions. 

Still, more studies have shown that CBD might be more effective as an add-on to proven treatments. CBD may also help treat the common side effects that come with antipsychotics.

CBD may also have drug interactions with antipsychotic medications. Hence, patients are discouraged from taking CBD and these substances together.

Alternative treatments to schizophrenia include the use of vitamins and supplements. Patients are also encouraged to try removing gluten from their diet.

However, CBD use is not advised when taking specific vitamins and supplements, such as folic acid.

Before adding CBD to their medication regimen, schizophrenia patients should first talk to their doctor.

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