Anxiety Disorder

Anxiety and stress are among the primary reasons for which patients say they use medical cannabis-second only to pain, Anxiety is a normal, but unpleasant sensation of apprehension when confronted with a new or threatening situation, and may be accompanied by physical symptoms. It may also occur in the absence of a triggering event. It is considered a disorder when it interferes which social or occupational functioning.

Anxiety disorders include generalized anxiety disorder(GAD), panic attacks, agoraphobia and social anxiety, obsessive-compulsive disorder, and acute stress disorder. While cannabis has been used to address symptoms of anxiety for thousands of years, caution is advised, as there is considerable evidence that large doses of cannabis trigger anxiety and even paranoia in susceptible individuals. Studies have also shown that females diagnosed with social anxiety disorders may be more prone to developing cannabis dependency.

Effectiveness

Cannabis can reduce or increase anxiety, depending on the variety, its chemistry and dose, the mind-set of the user, and the setting in which the cannabis is used. Understanding these variables increases the likelihood of relieving the symptoms of anxiety disorders. Cannabis has been described as "biphasic and bidirectional"- it can cause relaxation in some cases,  anxiety in others. These variations are typically tied to dose, with lower doses relieving anxiety, while higher doses may trigger a worsening of symptoms. Frequent high-dose THC users may develop chronic anxiety and troublesome worsening of other psychiatric problems, which paradoxically, they may attempt to "treat" with yet higher doses of THC. However, when THC and CBD were administered separately and together, CBD reduced anxiety associated with the use of THC. Low-dose preemptive use of CBD to reduce the likelihood of the onset of anxiety has also been studied. If you are going to use cannabis for anxiety, CBD is the best choice, but low doses of THC may also be effective, especially with cannabis-experienced patients, who are much less likely to become anxious.

Proposed Mechanism

Common symptoms of anxiety include worry, rumination, fear, apprehension, and tension. Anxiety is also a feature of other psychiatric conditions, including bipolar disorder, depression, and schizophrenia. It is thought that the endocannabinoid system may become pathologically activated in anxiety disorders. In particular, the density of the CB1 cannabinoid receptors found in the brain's amygdala, hippocampus, and anterior cingulate cortex—brain structures associated with anxiety--supports the idea that the endocannabinoid system regulates anxiety.

Limonene, a commonly occurring terpene in cannabis, is a known anxiolytic and increases levels of both dopamine and serotonin via the 5-HT1A receptor, boosting serotonin's presence in the prefrontal cortex and dopamine's in the hippocampus. Both of these areas in the brain are important in any therapeutic considerations of mood and anxiety. Linalool, another terpene found in many cannabis cultivars, is an established antidepressant and calming agent. 

Dosage

Both THC and CBD are effective for relieving symptoms of anxiety, but it may be more effective to use each cannabinoid separately. THC dosage for anxiety is successful at between 1 and 3 mg, while CBD dosage ranges between 2.5 and 10 mg. CBD dosage for panic disorders and phobias has ranged in studies, reaching up to 600 mg-but such high doses have been characterized as causing mild mental sedation. It is safe to assume that doses of up to 50 mg of CBD can be well tolerated by most patients.

Methods of Ingestion

ORAL: CBD can be used without psychoactive effect if taken in a spray or sublingually in a ratio of CBD:THC of 10:1 or higher, in doses of 5 mg CBD in the morning and again mid-afternoon. It can also be used throughout the day, as needed, but it is advised that the last dose of the day occurs before 5 p.m., as CBD can be wake-promoting. Light doses of THC (typically about 2.5 mg, but can range from 1 to 5 mg), taken sublingually, have relatively clear effects and are proven helpful to shift or elevate mood. This dose can be increased to 5 mg, if needed.

VAPORIZATION AND SMOKING: Smoking and vaping medical cannabis for anxiety are particularly effective, since the patient quickly learns precisely to titrate the proper dose. Here, 1 to 2.5 mg of vaporized or inhaled THC is recommended for faster onset than

with oral administration. Use the lowest effective dose to avoid the development of a tolerance whenever possible. Cannabis-naive patients should start with no more than 2.5 mg of THC (about a matchstick-head-sized piece of cannabis flower) and wait 10 to 15 minutes before adding more.

INDICATED CHEMOTYPES AND POPULAR

VARIETIES: Almost any type of cannabis can be used to relieve anxiety, even the most typically anxiogenic varieties, such as the Diesels and Hazes, provided that the dose is very tightly constrained. CBD varieties appear to be extremely effective for treating social anxiety and possibly phobias and panic disorders. Zeta and Cookies are excellent cultivars for shifting or improving mood and stimulating motivation while soothing anxiety. These cultivars are very potent, so a matchstick-head-sized piece can suffice for a daytime dose. Limonene is a known anxiolytic and antidepressant and is found in significant amounts in Tangerine Dream and OG Kush. "Purple" varieties are consistently noted to have effectiveness for sleep disorders, possibly because they are high in the calming and lightly sedative terpenes, linalool and myrcene. Linalool can be found in Bubba Kush and most Purples. Myrcene, however, should be avoided if suicidal ideation is present in the patient.

MICHAEL BACKES specializes in cannabis science and policy issues at a Southern California consultaney, which maintains clients throughout the United States. He previously founded the first evidence-based medical cannabis dispensary. Backes is active with Project CBD (dedicated to promoting research into the medical utility of cannabidio), the International Association for Cannabinoid Medicines, and the American Herbal Products Association's Cannabis Committee.

ANDREW WEIL, M. D. is a world-renowned leader and pioneer in the field of integrative medicine. Approximately 10 million of Dr. Weil's books have been sold, including Spontaneons Healing, 8 Weeks to Optimum Health, and Healthy Aging.

JACK D. McCUE, M.D. is professor emeritus of Medicine at the University of California, San Francisco. Dr. McCue has authored 14 books and monographs, plus 300 journal articles. He is the chief medical officer at Empower Clinics in
Portland, Oregon.