Medical Marijuana

Last Updated January 2021 | This article was created by familydoctor.org editorial staff and reviewed by Daron Gersch, MD, FAAFP

The use of medical marijuana can be a debated topic. People can have strong feelings about whether it’s right or wrong to use. Other people wonder if it’s legal. Note that medical marijuana isn’t the same as marijuana for recreational use.

U.S. federal law says it’s illegal to use whole plant cannabis sativa, or any parts of the plant, for any reason. That’s the plant medical marijuana comes from. However, some states have made medical marijuana legal to use for some health conditions. These states have very strict rules and laws about when and how it can be used. They also regulate how it can be bought. The rules and laws differ from state to state.

Doctors and researchers are still investigating the pros and cons of medical marijuana. There is much research still to be done, but some results show medical marijuana may have a positive effect on certain medical conditions.

Path to improved health

It all starts with the cannabis sativa plant. That is the plant medical marijuana comes from. The plant contains many chemicals, called cannabinoids. Two of these cannabinoids can be used to make medical marijuana. They are cannabidiol (known as CBD) and delta-9-tetrahydrocannabinol (known as THC). THC is the chemical that causes the “high” many people get with marijuana.

A hemp plant is the same as the cannabis sativa plant. However, hemp is marijuana that contains 0.3% or less THC. Federal law says that CBD made from the hemp plant that contains less than 0.3% of THC is legal to use. That’s because the THC level is so low that you won’t experience the “high” of the marijuana.

Medical marijuana is available only for people who have certain health conditions. The U.S. Food & Drug Administration (FDA) has approved its use for people who have cancer and have developed nausea because of chemotherapy. The FDA also has approved its use as an appetite stimulant for people who have HIV or AIDS. Additionally, medical marijuana may also improve the side effects of the following conditions:

If you have one of these conditions and want to try medical marijuana, you’ll find it has many forms. It’s available as a pill to swallow, a lotion or oil to rub onto your skin, a liquid to place under your tongue, or as an oil to use in a vaporizer. Each form takes a different amount of time to affect your body. In general, you’ll feel the effects of oil in a vaporizer that fastest. It may take a few hours to feel the effects of a pill.

Talk with your doctor if you’re thinking of trying medical marijuana. Be aware that not all doctors in states where it’s legal will encourage you to try it. However, some may recommend it if you’ve tried other treatment options that haven’t worked.

In order to purchase the medical marijuana, the rules vary by state. Some states require a note from your doctor. You can buy it when you take this note to a dispensary (a store where you can buy it). Some states add your name to a master list so you can buy from any approved seller. And some states require a medical marijuana ID card.

Things to consider

Doctors are still studying the effects of taking medical marijuana long term. You may become addicted to it, have memory loss, have hallucinations (hear or see things that aren’t real), or develop bronchitis. However, there are known side effects for taking it, even just once. Those include:

  • Dizziness
  • Bloodshot eyes
  • Fast heart rate
  • Low blood pressure
  • Lack of coordination

Some people need to avoid taking medical marijuana, even if they have one of the health conditions it treats. They include people who are pregnant, people with heart disease, and children under 18 years of age.

Questions for your doctor

  • Is medical marijuana legal in my state?
  • Am I a candidate for taking medical marijuana?
  • What form is best for me?
  • Will I experience side effects?
  • Where can I buy it?
  • Do I need a special ID or paperwork to buy it?
  • How long can I take it?