Drugs containing cannabinoids may be helpful in treating certain rare forms of epilepsy, nausea and vomiting associated with cancer chemotherapy, and loss of appetite and weight loss associated with HIV/AIDS. In addition, some evidence suggests modest benefits of cannabis or cannabinoids for chronic pain and multiple sclerosis symptoms. Cannabis isn’t helpful for glaucoma. Research on cannabis or cannabinoids for other conditions is in its early stages.

• Pain

• Helping To Decrease Opioid Use

• Anxiety

• Epilepsy

• Glaucoma

• HIV/AIDS Symptoms

• Inflammatory Bowel Disease

• Irritable Bowel Syndrome

• Movement Disorders Due to Tourette Syndrome

• Multiple Sclerosis

• Nausea and Vomiting Related to Cancer Chemotherapy

• Posttraumatic Stress Disorder (PTSD)

• Sleep Problems

CBD, THC and other cannabinoids act on certain receptors in the body. The human body produces some cannabinoid molecules on its own, called endocannabinoids and has receptors for these them. Two of the most well studied cannabinoid receptors are the CB1 and CB2 receptors.

• CB1 receptors are found mostly in the central nervous system with some in other parts of the body. CB1 receptors affect things like movement, pain, mood, and appetite.
• CB2 receptors are more common in the immune system and digestive tract. CB2 receptors can affect inflammation and pain.

Products (like pills, oils, creams, etc.) that contain both CBD and THC can act on both CB receptors and can potentially affect the body’s own endocannabinoids.

CBD, THC and other cannabinoids can be used in a variety of ways. They can be taken by mouth (capsules, tinctures etc.), applied on the skin as a cream or an oil, breathed in as a vapor, or used as a rectal suppository.

Allowable Forms of Medical Cannabidiol

• Oral forms - tablets, capsules, liquids, tinctures and sublingual forms
• Topical forms - gels, ointments, creams, lotions and transdermal patches
• Nebulizable inhaled forms
• Suppositories - rectal and vaginal
• Vaporization

Potential Side Effects of CBD: Studies on the safety of CBD have found that it is generally well-tolerated. So far there have been no significant side effects among people who use CBD. The most common side effects of CBD are:

• Fatigue/tiredness
• Diarrhea
• Changes in appetite or weight
• Dry mouth

Special Considerations for Use of CBD:

• There is not currently enough reliable information about the safety of taking CBD while pregnant or breastfeeding. CBD is not recommended for use by pregnant or breast-feeding women.

CBD Drug Interactions:

• CBD is broken down by the liver so it’s possible it could interact with other medications that the liver breaks down. This can include; ketoconazole, itraconazole, ritonavir, clarithromycin, phenobarbital, rifampicin, carbamazepine, phenytoin, SSRIs, tricyclic antidepressants, beta blockers, some antibiotics such as cyclosporine, warfarin, diclofenac, some kinds of cancer treatment drugs and clobazam.

Some of these interactions are based on research only and so you should talk with your healthcare provider about your medications.

The Most Common Side Effects of THC are:

• Impaired attention or short-term memory
• Drowsiness, dizziness or lightheadedness
• Dry mouth
• Nausea
• Sense of well-being (euphoria), and general changes in mood
• Heightened awareness
• Increased appetite
• In high doses: anxiety, panic, confusion, or transient psychosis

Special Considerations for the use of THC:

• There is not currently enough data about the safety of using THC while pregnant or breastfeeding. THC should not be used by pregnant or breastfeeding women.
• THC should be used with caution in those with prior psychiatric diseases or mental illness.
• THC should be used with caution in kids because it can impact brain development.
• Patients using THC should not drive or do anything that could be considered dangerous until they understand their reaction to THC.

THC Drug Interactions:

• THC may interact with several medications including; clozapine, duloxetine, naproxen, cyclobenzaprine, olanzapine, haloperidol, chlorpromazine, warfarin, diclofenac, some antibiotics, alcohol, barbiturates, and benzodiazepines
• Alcohol use may increase serum THC levels
• Some studies have shown potential nausea and cramping with disulfiram and metronidazole.

You should talk with your doctor about how THC might affect your other medications.

Special Considerations for the use of Cannabis products: (Generally contain both THC and CBD)

• Patients with a history of hypersensitivity to cannabis should not use medical cannabis.
• Products should be used with caution in those with severe acute heart, immune, liver or kidney disease
• Cannabis products may exacerbate arrhythmia (abnormal heart rhythms)

Just like any new treatment, patients should consider the health benefits, side effects, and risks of CBD, THC, and other cannabinoids before using them. The dose and form (pill, oil, cream, vapor etc.) can vary depending on the condition being treated. If you experience side effects, stop treatment and talk to your healthcare provider immediately.

• Research has been done on the effects of cannabis or cannabinoids on chronic pain, particularly neuropathic pain (pain associated with nerve injury or damage).
• A 2018 review looked at 47 studies (4,743 participants) of cannabis or cannabinoids for various types of chronic pain other than cancer pain and found evidence of a small benefit. Twenty-nine percent of people taking cannabis/cannabinoids had a 30 percent reduction in their pain whereas 26 percent of those taking a placebo (an inactive substance) did. The difference may be too small to be meaningful to patients. Adverse events (side effects) were more common among people taking cannabis/cannabinoids than those taking placebos.
• A 2018 review of 16 studies of cannabis-based medicines for neuropathic pain, most of which tested a cannabinoid preparation called nabiximols (brand name Sativex; a mouth spray containing both THC and CBD that is approved in some countries but not in the United States), found low- to moderate-quality evidence that these medicines produced better pain relief than placebos did. However, the data could not be considered reliable because the studies included small numbers of people and may have been biased. People taking cannabis-based medicines were more likely than those taking placebos to drop out of studies because of side effects.
• A 2015 review of 28 studies (2,454 participants) of cannabinoids in which chronic pain was assessed found the studies generally showed improvements in pain measures in people taking cannabinoids, but these did not reach statistical significance in most of the studies. However, the average number of patients who reported at least a 30 percent reduction in pain was greater with cannabinoids than with placebo.

Pain management improves a patient’s quality of life throughout all stages of cancer. Through the study of cannabinoid receptors, endocannabinoids, and synthetic agonists and antagonists, the mechanisms of cannabinoid-induced analgesia have been analyzed. The CB1 receptor is found in the central nervous system (CNS) and in peripheral nerve terminals. CB2 receptors are located mainly in peripheral tissue and are expressed in only low amounts in the CNS. Whereas only CB1 agonists exert analgesic activity in the CNS, both CB1 and CB2 agonists have analgesic activity in peripheral tissue.

Cancer pain results from inflammation, invasion of bone or other pain-sensitive structures, or nerve injury. When cancer pain is severe and persistent, it is often resistant to treatment with opioids.

Two studies examined the effects of oral delta-9-THC on cancer pain. The first, a double-blind, placebo-controlled study involving ten patients, measured both pain intensity and pain relief. It was reported that 15 mg and 20 mg doses of the cannabinoid delta-9-THC were associated with substantial analgesic effects, with antiemetic effects and appetite stimulation.

In a follow-up, single-dose study involving 36 patients, it was reported that 10 mg doses of delta-9-THC produced analgesic effects during a 7-hour observation period that were comparable to 60 mg doses of codeine, and 20 mg doses of delta-9-THC induced effects equivalent to 120 mg doses of codeine.[59] Higher doses of THC were found to be more sedating than codeine.

Another study examined the effects of a plant extract with controlled cannabinoid content in an oromucosal spray. In a multicenter, double-blind, placebo-controlled study, the THC:CBD nabiximols extract and THC extract alone were compared in the analgesic management of patients with advanced cancer and with moderate-to-severe cancer-related pain. Patients were assigned to one of three treatment groups: THC:CBD extract, THC extract, or placebo. The researchers concluded that the THC:CBD extract was efficacious for pain relief in advanced cancer patients whose pain was not fully relieved by strong opioids. In a randomized, placebo-controlled, graded-dose trial, opioid-treated cancer patients with poorly controlled chronic pain demonstrated significantly better control of pain and sleep disruption with THC:CBD oromucosal spray at lower doses (1–4 and 6–10 sprays/d), compared with placebo. Adverse events were dose related, with only the high-dose group (11–16 sprays/d) comparing unfavorably with the placebo arm. These studies provide promising evidence of an adjuvant analgesic effect of THC:CBD in this opioid-refractory patient population and may provide an opportunity to address this significant clinical challenge. An open-label extension study of 43 patients who had participated in the randomized trial found that some patients continued to obtain relief of their cancer-related pain with long-term use of the THC:CBD oromucosal spray without increasing their dose of the spray or the dose of their other analgesics.

An observational study assessed the effectiveness of nabilone in advanced cancer patients who were experiencing pain and other symptoms (anorexia, depression, and anxiety). The researchers reported that patients who used nabilone experienced improved management of pain, nausea, anxiety, and distress when compared with untreated patients. Nabilone was also associated with a decreased use of opioids, nonsteroidal anti-inflammatory drugs, tricyclic antidepressants, gabapentin, dexamethasone, metoclopramide, and ondansetron.

• There’s evidence from studies in animals that administering THC along with opioids may make it possible to control pain with a smaller dose of opioids.
• A 2017 review looked at studies in people in which cannabinoids were administered along with opioids to treat pain. These studies were designed to determine whether cannabinoids could make it possible to control pain with smaller amounts of opioids. There were 9 studies (750 total participants), of which 3 (642 participants) used a high-quality study design in which participants were randomly assigned to receive cannabinoids or a placebo. The results were inconsistent, and none of the high-quality studies indicated that cannabinoids could lead to decreased opioid use.
• Researchers have looked at statistical data on groups of people to see whether access to cannabis (for example, through “medical marijuana laws”—state laws that allow patients with certain medical conditions to get access to cannabis)—is linked with changes in opioid use or with changes in harm associated with opioids. The findings have been inconsistent.
  • States with medical marijuana laws were found to have lower prescription rates both for opioids and for all drugs that cannabis could substitute for among people on Medicare. However, data from a national survey (not limited to people on Medicare) showed that users of medical marijuana were more likely than nonusers to report taking prescription drugs.
  • An analysis of data from 1999 to 2010 indicated that states with medical marijuana laws had lower death rates from overdoses of opioid pain medicines, but when a similar analysis was extended through 2017, it showed higher death rates from this kind of overdose.
  • An analysis of survey data from 2004 to 2014 found that passing of medical marijuana laws was not associated with less nonmedical prescription opioid use. Thus, people with access to medical marijuana did not appear to be substituting it for prescription opioids.

Patients often experience mood elevation after exposure to Cannabis, depending on their previous experience. In a five-patient case series of inhaled Cannabis that examined analgesic effects in chronic pain, it was reported that patients who self-administered Cannabis had improved mood, improved sense of well-being, and less anxiety.

Another common effect of Cannabis is sleepiness. A small placebo-controlled study of dronabinol in cancer patients with altered chemosensory perception also noted increased quality of sleep and relaxation in THC-treated patients.

Seventy-four patients with newly diagnosed head and neck cancer self-described as current Cannabis users were matched to 74 nonusers in a Canadian study investigating quality of life using the EuroQol-5D and Edmonton Symptom Assessment System instruments. Cannabis users had significantly lower scores in the anxiety/depression (difference, 0.74; 95% CI, 0.557–0.930) and pain/discomfort (difference, 0.29; 95% CI, 0.037–1.541) domains. Cannabis users were also less tired, had more appetite, and better general well-being.

Cannabinoids, primarily CBD, have been studied for the treatment of seizures associated with forms of epilepsy that are difficult to control with other medicines. Epidiolex (oral CBD) has been approved by the FDA for the treatment of seizures associated with two epileptic encephalopathies: Lennox-Gastaut syndrome and Dravet syndrome. (Epileptic encephalopathies are a group of seizure disorders that start in childhood and involve frequent seizures along with severe impairments in cognitive development.) Not enough research has been done on cannabinoids for other, more common forms of epilepsy to allow conclusions to be reached about whether they’re helpful for these conditions.

• Glaucoma is a group of diseases that can damage the eye’s optic nerve, leading to vision loss and blindness. Early treatment can often prevent severe loss of vision. Lowering pressure in the eye can slow progression of the disease.
• Studies conducted in the 1970s and 1980s showed that cannabis or substances derived from it could lower pressure in the eye, but not as effectively as treatments already in use. One limitation of cannabis-based products is that they only affect pressure in the eye for a short period of time.
• A recent animal study showed that CBD, applied directly to the eye, may cause an undesirable increase in pressure in the eye.

• Unintentional weight loss can be a problem for people with HIV/AIDS. In 1992, the FDA approved the cannabinoid dronabinol for the treatment of loss of appetite associated with weight loss in people with HIV/AIDS. This approval was based primarily on a study of 139 people that assessed effects of dronabinol on appetite and weight changes.
• There have been a few other studies of cannabis or cannabinoids for appetite and weight loss in people with HIV/AIDS, but they were short and only included small numbers of people, and their results may have been biased. Overall, the evidence that cannabis/cannabinoids are beneficial in people with HIV/AIDS is limited.

Where does cannabis fit in? The endocannabinoid system and the gut

The endocannabinoid system (ECS) is a network of receptors and enzymes related to pain, appetite, memory and mood. ECS is likely the communication link between the gut and the brain, interacting with the body’s central nervous system (CNS) and enteric nervous system (ENS), which extends from the oesophagus to the rectum. The ENS uses the same receptors, neurons, and neurotransmitters as the CNS.

The ECS modulates inflammation, regulates digestion, and regulates communication with the brain. Its receptors interact with cannabinoids, found in cannabis and other plants such as black pepper, cloves, hops, ginseng, black truffles, and dark chocolate. Our body makes its own cannabinoids (called endocannabinoids) that act on these receptors.

In IBD, the endocannabinoid system is compromised, further reinforcing the case for cannabis and CBD-based therapies. Cannabis use is already high among IBD patients, as numerous surveys have shown.

Several cannabis/cannabinoid preparations have been studied for multiple sclerosis symptoms, including dronabinol, nabilone, cannabis extract, nabiximols (brand name Sativex; a mouth spray containing THC and CBD that is approved in more than 25 countries outside the United States), and smoked cannabis.

• A review of 17 studies of a variety of cannabinoid preparations with 3,161 total participants indicated that cannabinoids caused a small improvement in spasticity (as assessed by the patient), pain, and bladder problems in people with multiple sclerosis, but cannabinoids didn’t significantly improve spasticity when measured by objective tests.
• A review of 6 placebo-controlled clinical trials with 1,134 total participants concluded that cannabinoids (nabiximols, dronabinol, and THC/CBD) were associated with a greater average improvement on the Ashworth scale for spasticity in multiple sclerosis patients compared with placebo, although this did not reach statistical significance.
• Evidence-based guidelines issued in 2014 by the American Academy of Neurology concluded that nabiximols is probably effective for improving subjective spasticity symptoms, probably ineffective for reducing objective spasticity measures or bladder incontinence, and possibly ineffective for reducing multiple sclerosis–related tremor. Based on two small studies, the guidelines concluded that the data are inadequate to evaluate the effects of smoked cannabis in people with multiple sclerosis.
• A 2010 analysis of 3 studies (666 participants) of nabiximols in people with multiple sclerosis and spasticity found that nabiximols reduced subjective spasticity, usually within 3 weeks, and that about one-third of people given nabiximols as an addition to other treatment would have at least a 30 percent improvement in spasticity. Nabiximols appeared to be reasonably safe.

An additional concern with "medical marijuana" is that little is known about the long-term impact of its use by people with health- and/or age-related vulnerabilities—such as older adults or people with cancer, AIDS, cardiovascular disease, multiple sclerosis, or other neurodegenerative diseases. Further research will be needed to determine whether people whose health has been compromised by disease or its treatment (e.g., chemotherapy) are at greater risk for adverse health outcomes from marijuana use.

Some schools, hospitals, and places of employment require drug testing. There are a number of ways this can be done, including pre-employment testing, random testing, reasonable suspicion/cause testing, post-accident testing, return to duty testing, and followup testing. This usually involves collecting urine samples to test for drugs such as marijuana, cocaine, amphetamines, PCP, and opioids.

Drug tests vary, depending on the type of drug being tested for and the type of specimen being collected. Urine, hair, saliva (oral fluid), or sweat can be used as test specimens.

Mandatory guidelines for federal workplace drug testing of urine specimens were established in 1988 and updated in 2017. In 2019, Congress allowed federal executive branch agencies to also collect and test oral fluid specimens as part of their drug testing programs.

Drug Testing and Workplace Issues

Studies suggest that many adults who use illegal drugs are employed full or part time. In addition, when compared with those who do not use substances, employees who use substances are more likely to:

• Change jobs frequently.
• Be late to or absent from work.
• Be less productive.
• Be involved in a workplace accident and potentially harm others.
• File a workers’ compensation claim.

Employers who have implemented drug-free workplace programs have important experiences to share.

• Employers with successful drug-free workplace programs report improvements in morale and productivity and decreases in absenteeism, accidents, downtime, turnover, and theft.
• Employers with long-standing programs report better health status among employees and family members and reduced healthcare costs.
• Some organizations with drug-free workplace programs qualify for incentives, such as decreased costs associated with short- and long-term disability and workers’ compensation.