The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid if allergic or sensitive to cannabinoids or to plants of the Cannabaceae family. Asthma, hives, pink eye, and runny or stuffy nose have been reported.
Side Effects and Warnings
Cannabinoids are likely safe when used for specific conditions at the recommended doses for the recommended amount of time.
Side effects have mostly been linked to THC, the active ingredient in Cannabis sativa. Dizziness is a common side effect. Marijuana may have effects on almost every organ system in the body, including the central nervous, heart, endocrine, and immune systems.
Use cautiously with alcohol. Combining alcohol and CBD may cause significantly low blood alcohol levels compared to alcohol alone, though similar effects may occur.
Marijuana may increase the risk of bleeding. Caution is advised in people with bleeding disorders or those taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
Marijuana may affect blood sugar levels. Caution is advised in people with diabetes or blood sugar problems, and in those taking drugs, herbs, or supplements that affect blood sugar. Blood sugar levels may need to be monitored by a qualified healthcare professional, including a pharmacist, and medication adjustments may be necessary.
Marijuana may cause low blood pressure. Caution is advised in people who have blood pressure disorders or those taking drugs or herbs and supplements that lower blood pressure.
Use cautiously in people who have liver disease or those using agents toxic to the liver.
Use cautiously in people who are taking barbiturates, antipyrine, or central nervous system (CNS) depressants.
Marijuana may interfere with the way the body processes certain agents using the liver's cytochrome P450 enzyme system. As a result, the levels of these agents may be increased in the blood and may cause increased effects or potentially serious adverse reactions. People using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
Use cautiously in people who are on estrogen therapy.
Use cautiously in people who have immune disorders or those taking agents that may affect the immune system.
Use cautiously in people who are taking p-glycoprotein-regulated drugs.
Use cautiously in people who have a history of drug abuse or addiction. Marijuana may be addictive.
Use cautiously in people who have or are at risk of eye problems. Marijuana may cause eye problems and dry eyes, and it may increase eye pressure.
Use cautiously when consuming foods or supplements that contain cannabis seeds or oil. These products may contain a high level of THC that may trigger a positive drug screen.
Use cautiously in people who are at risk of seizure or those using antiseizure drugs. Marijuana may cause seizures.
Use cautiously in people who have or are at risk of heart disease. Marijuana may cause abnormal heartbeat, disrupted blood flow to organs (kidney, spleen), heart attack, and heart failure.
Use cautiously in people who have learning disabilities or attention-deficit hyperactivity disorder (ADHD). Marijuana may cause problems with attention, learning, memory, organization, planning, problem solving, and other brain functions.
Use cautiously in people at risk of skin problems. Marijuana may cause hives, patches in the mouth, and skin itching.
Use cautiously in people with stomach disorders. Marijuana may cause stomach problems such as a bad taste, burning or swelling tongue, diarrhea, dry mouth, increased appetite, indigestion, mouth ulcers, nausea, pain, and vomiting.
Use cautiously in people who have or are at risk of musculoskeletal disorders. Marijuana may cause bone problems, increased risk of side effects linked to musculoskeletal or connective tissue disorders, falls, muscle problems (pain, twitching, or weakness), numbness, recurrence in multiple sclerosis, reduced coordination, restlessness, and speech disorders.
Drowsiness or sedation may occur. Use caution if driving or operating heavy machinery.
Use cautiously in all otherwise healthy people who are not taking any medications. Marijuana may cause disorientation, dizziness, headaches, fatigue, a feeling of intoxication, lightheadedness, and reduced attention.
Use cautiously in people who have or are at risk of ear problems. Marijuana may cause ear problems.
Avoid if allergic or sensitive to cannabinoids or to plants of the Cannabaceae family. Asthma, hives, pinkeye, and runny or stuffy nose have been reported.
Avoid in women who are pregnant, breastfeeding, or trying to get pregnant. Marijuana may have serious risks and may cause low birthweight or abnormalities in the baby.
Avoid long-term use in people who have or are at risk of lung problems, such as asthma or byssinosis (a disease caused by breathing dust). Marijuana may cause bronchitis, coughing, lung cysts, phlegm, reduced lung density, and wheezing.
Avoid using cannabis products that have been obtained illegally. These products may contain unknown and possibly harmful ingredients, such as the animal tranquilizer PCP.
Avoid inhaling cannabis, due to increased risks of lung cancer, emphysema (chronic lung disease), and spontaneous pneumothorax (collapsed lung).
Avoid injecting cannabis into the veins. Cannabis sativa may be extremely toxic.
Avoid using in children or adolescents. Marijuana may affect brain development in the young.
Avoid using in people who have or are at risk of mental illness. Marijuana may cause anxiety and psychotic-like symptoms. It may also increase the risk of aggression, bipolar disorder, delusions, depression, hallucinations, lack of energy or motivation, and suicidal thoughts.
Avoid using before driving motorized vehicles. Marijuana may increase the risk of collision, and when combined with alcohol, it may affect alertness and driving performance.
Marijuana may also cause blood rush or dizziness when standing, a burning sensation, cannabis arteritis (reduced blood flow to feet and legs), changes in brain structure, changes in chromosomes, changes in erectile function, changes in quality of life, confusion, detachment from surroundings, difficulty concentrating, dysphoria (feeling unhappy or unwell), euphoria (feeling of happiness or well-being), forgetfulness, hoarseness, increased risk of male cancers, liver problems (damage, disorders, or poisoning), panic, paranoid thinking, problems with bowel movements, psychiatric problems, reduced saliva, reduced sperm production, risky behaviors (unprotected sex), sudden stomach upset, sweating, thirst, throat irritation, urinary tract infection, and weight gain.
Pregnancy and Breastfeeding
Avoid using marijuana in women who are pregnant, breastfeeding, or trying to get pregnant. Research strongly suggests that marijuana may have serious risks for the child, including abnormalities, cancer, development problems, increased leukemia risk, low birthweight, and reduced attention skills. Cannabis may affect the mother's judgment and ability to care for the child, and it should not be smoked around infants or children. Cannabis may be passed to babies through breast milk.
This evidence-based monograph was prepared by The Natural Standard Research Collaboration