The class of psychotropic drugs is a big one, and you may be surprised by some of the substances included in this group. Psychotropic drugs affect your mental state, including your thoughts, perceptions, mood and behavior.

When you hear the words ‘psychotropic drugs,’ what comes to mind might be something like LSD or mescaline. Those drugs fall broadly into that category. But so does caffeine. 

What Are Psychotropic Drugs?

For the most part, when we talk about psychotropic drugs, we talk about medications used to treat various mental health disorders. These include anti-anxiety medications, antidepressants, antipsychotics and stimulants. These drugs are also used to treat sleep disorders and, in some cases, to treat pain. A few widely used psychotropic drugs are Adderall, Ritalin, Ativan, Xanax, Elavil, Lexapro and Cymbalta — and that’s just a few from a long list.

Psychoactive Drugs

Most psychoactive drugs work by altering the brain’s neurotransmitters. These chemicals ferry messages from one neuron, or brain cell, to another. Serotonin, dopamine, acetylcholine and norepinephrine are a few neurotransmitters in the body.

Imbalanced Neurotransmitters

Health issues can arise when neurotransmitters don’t function properly — like when too much or too little of a neurotransmitter is produced or when the cell that receives the chemical message doesn’t take it up as it should. Imbalanced neurotransmitters are behind many health problems, including depression, attention deficit hyperactivity disorder (ADHD), anxiety, Parkinson’s disease and Alzheimer’s disease.

Read More: 5 Essential Neurotransmitters for Everyday Life

Psychotropic Medications

Psychotropic medications work in several ways to restore the balance of neurotransmitters and, hopefully, health. These drugs can block enzymes that break down certain neurotransmitters, helping to keep those neurotransmitters in the system. This is how some medications for Alzheimer’s and Parkinson’s disease work. Regarding depression, some medications prevent receptor cells from taking up a neurotransmitter.

Depression and Serotonin Levels

Selective serotonin reuptake inhibitors, such as Prozac, Paxil, Zoloft and others, are examples of this type of drug. (They’re called “selective” because they operate selectively on serotonin, not on just any neurotransmitter.) They keep serotonin from being reabsorbed by the neurons, leaving more in circulation to deliver chemical messages.

Read More: These 5 Animals Trip on Psychedelic and Psychoactive Drugs, Too

Antipsychotics

Antipsychotics are typically used to treat schizophrenia and delirium. Sometimes these drugs are used to treat depression, mania and dementia as well. Like other psychotropic medications, antipsychotics work by tinkering with neurotransmitters. They block specific dopamine receptors and certain serotonin receptors while stimulating others. Antipsychotics are occasionally used to treat bipolar disorder. Lithium, while not an antipsychotic, has long been used to treat bipolar disorder. It works by blocking the release of norepinephrine.

Stimulants

Stimulants are also classed as psychotropic drugs. Stimulants such as Ritalin and Adderall are sometimes used to treat narcolepsy, a sleep disorder that causes people to fall asleep unexpectedly. Ritalin and Adderall are better known for treating ADHD. These drugs increase the levels of dopamine and norepinephrine in the brain by blocking their reuptake.

Benzodiazepines

Benzodiazepines, such as Ativan and Xanax, are used to treat anxiety and insomnia. They have a sedative effect and work by boosting a neurotransmitter known as gamma-aminobutyric acid (GABA). GABA calms the nervous system.

Opioids

Opioids are often classed as psychotropic drugs as well, but they work in a slightly different way. Opioids bind to opioid receptors in the brain and block pain signals sent from the body. These pain receptors then release dopamine, which causes feelings of euphoria.

So yes, psychotropic drugs most definitely mess with your mind, but for the most part, it’s all for a good cause.

Read More: Important Habits to Keep Your Brain Healthy