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Hemp

Hemp is a plant that contains chemicals called cannabinoids, which affect the central nervous system. Cannabinoids are found in the highest concentration in the leaves and flowers of the plant, which are used to make medicine. Some people use hemp-derived marijuana as a recreational drug to create a sense of well-being or to alter sensory perceptions. Marijuana is either taken orally or smoked for this purpose. Marijuana is also taken orally for medicinal purposes. One cannabinoid, tetrahydrocannabinol (THC), is used in America in the prescription drug dronabinol, which is used to treat weight loss or loss of appetite due to AIDS, as well as nausea and vomiting due to chemotherapy for cancer. Cannabinoids are at least as effective as some conventional anti-nausea drugs including prochlorperazine, metoclopramide, chlorpromazine and thiethylperazine.

Cannabinoids from hemp appear to be similar to codeine in the treatment of pain. However, the extreme insomnia and other effects on the central nervous system make cannabinoids inadvisable as painkillers. Other cannabinoids derived from hemp have been used orally to treat symptoms of multiple sclerosis. Some people inhale hemp products for medicinal purposes. Hemp and hemp-derived products are smoked to treat nausea, glaucoma, inflammation of the mucous membranes, leprosy, fever, dandruff, hemorrhoids, obesity, asthma, urinary tract infections, coughs, anorexia associated with weight loss in AIDS patients, pain and multiple sclerosis, as well as to stimulate appetite. They are also smoked after liver transplants to weaken the immune system and reduce the risk of donor organ rejection. Hemp contains chemicals that work by binding to specific receptors in the brain and nerves.

Hemp is potentially effective for the following applications

  • Improving appetite in AIDS patients: Smoking hemp appears to stimulate appetite in AIDS patients. Hemp cigarettes can also cause weight gain in HIV patients who are also taking indinavir or nelfinavir.
  • Glaucoma: Smoking hemp appears to reduce the pressure inside the eye in patients suffering from glaucoma. However, it also appears to reduce blood flow to the optic nerve. It is not yet known whether hemp can improve the function of the eye.
  • Multiple sclerosis: Hemp, when smoked or when the cannabinoids are taken orally, appears to be effective in treating the tension and shakiness associated with multiple sclerosis.

There is not enough scientific data to draw a conclusion about the effectiveness of hemp products for dandruff, hemorrhoids, obesity, asthma, urinary tract infections, leprosy and nerve pain, as well as use to prevent donor organ rejection after kidney transplants. Further scientific research is needed to evaluate the effectiveness of hemp products in these applications.

Safety and side effects

The cannabinoid dronabinol, which is found in hemp, is probably safe and harmless when taken orally as a prescription drug. In America, dronabinol is an approved medication. Hemp may not be safe and harmless when taken orally or smoked. It is classified as an illegal substance in most countries around the world. The use of hemp can cause dry mouth, nausea, vomiting, dry or red eyes, heart and blood pressure problems, lung problems, impaired mental function, headaches, dizziness, numbness, panic reactions, hallucinations, flashbacks, depression and sexual problems.

Precautions and warnings

Pregnancy and breastfeeding: Smoking hemp or taking hemp orally is not safe during pregnancy. Hemp crosses the placenta and can slow the growth of the fetus. The use of hemp during pregnancy has also been linked to childhood leukemia. While breastfeeding, smoking or oral ingestion of hemp is probably not safe and harmless. The dronabinol (THC) in hemp passes into breast milk. Hemp could cause heart disease such as rapid heartbeat and short-term high blood pressure. A weakened immune system can also occur. Cannabinoids in hemp can weaken the immune system, making it harder for the body to fight infections. Another problem is lung disease: short-term use of hemp can aggravate lung problems. Regular, long-term use of hemp has been linked to several cases of emphysema, a lung disease.

In addition, seizures: Hemp might worsen seizures in some people, while it might help control seizures in others. Note in the context of surgery: Hemp can slow down the function of the central nervous system. There are concerns that hemp may reduce central nervous system function too much when combined with anesthetics or other medications used during or after surgery. For this reason, the use of hemp should be discontinued at least 2 weeks before upcoming operations.

Interactions

Hemp should not be used in combination with the following medications

Sedatives (barbiturates and CNS suppressants)

Hemp may cause drowsiness and dizziness. Drugs that cause drowsiness are called sedatives. The use of hemp in conjunction with sedatives could cause excessive drowsiness.

Theophylline

The use of hemp could reduce the effects of theophylline. However, there is not enough information to say whether this is a major cause for concern.

Care should be taken when combining hemp with the following medications:

Disulfiram

Disulfiram may interact with hemp. The use of hemp in combination with disulfiram can cause agitation, sleep problems and irritability.

Fluoxetine

The use of hemp in combination with fluoxetine (Prozac) may cause nervousness, restlessness and agitation. This is also known as hypomania. Care should be taken when combining hemp with the following medications:

Warfarin

The use of hemp could increase the effects of warfarin. Smoking hemp while taking warfarin could increase the risk of bruising and bleeding.

Oral dosage

The prescription product dronabinol, which contains one of hemp's chemicals, is used in doses of 5 to 15 mg every 2 to 4 hours for nausea and vomiting due to cancer chemotherapy and in doses of 2.5 to 10 mg twice daily to improve appetite in AIDS patients. Current scientific information suggests that smoking or inhaling hemp may not be safe and harmless.

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