Heroin is not only a central nervous system depressant, it is also linked to mental health problems like depression.

Article at a Glance:

  • Heroin is an opioid that is considered a central nervous system depressant.
  • It works by slowing down activity in the central nervous system.
  • Mental health problems like depression are risk factors for heroin abuse and can result from heroin abuse as well.

Is Heroin a Stimulant?

Heroin, a Schedule I illicit opioid, is not a stimulant. In fact, it is the opposite of a stimulant: instead of revving up the central nervous system, heroin suppresses it.

Sometimes, heroin is combined with illicit stimulants like cocaine and taken as a speedball. A person may mix the two so that the cocaine combats the sedating effects of heroin.

Is Heroin a Depressant?

Heroin is a central nervous system depressant. Like other opioids, it slows down, or depresses, activity in the central nervous system.

The drug achieves its effects by binding to mu-opioid receptors in the brain. It also targets the brain’s reward system, leading to a compulsion to take the drug, which can result in addiction.

Prescription Opioids & Heroin

Heroin is an illegal opioid drug derived from morphine. Opioids are powerful pain-relieving medications that are sometimes referred to as depressants. This is largely due to the discernable effects of the drugs on the body, including slowed breathing and heart rate. This is especially true when taken at high doses or with other depressants like benzodiazepines, sleep medications or barbiturates.

A person who takes prescription opioids, especially nonmedically, is at an increased risk of heroin abuse. About 86% of people who abuse heroin previously abused prescription opioids that they generally obtained from family, friends, or their own prescriptions. Overall, around 4% of people who abuse prescription opioids will progress to abusing heroin.

Heroin’s Depressant Properties

Unlike benzodiazepines, barbiturates and other prescription sedatives that slow brain activity to treat anxiety and sleep disorders, opioids — including heroin — affect brain functioning by attaching to and activating mu-opioid receptors to regulate pain.

In addition to blocking pain, opioid receptors are involved in feelings of pleasure and in controlling heart rate, sleeping and breathing. This means that while heroin dulls pain and offers a rapid and intense rush, it may also impair cognitive functioning, increase sedation, and slow certain autonomic functions, such as those that control a person’s respiratory rate. In other words, it may depress the brain’s cognitive function and a person’s ability to breathe.

After an initial surge of pleasure or euphoria, people who use heroin often experience heaviness in their arms and legs and clouded mental functioning. Another side effect of heroin use is “going on the nod,” a back-and-forth state of consciousness and semi-consciousness.

People who use heroin chronically can experience many adverse reactions affecting the body and the mind. Mental health problems such as depression can occur with long-term heroin use.

Heroin and Depression

Long-term opioid abuse is closely linked to mood disorders like depression and higher rates of anxiety disorders. Heroin can cause depression, mood changes, suicidal behavior, psychological dependence and addiction. Further, pre-existing mental health problems like depression are linked to the development of substance abuse problems in the first place.

Various types of drugs can trigger depression, a mood disorder characterized by fatigue, hopelessness and suicidal thoughts, but that does not mean that these drugs are depressants. Depressants slow brain activity by increasing the activity of the chemical gamma-aminobutyric acid, or GABA.

When a person begins to use more and more heroin to achieve the same initial transient “high,” the brain quickly adapts to the constant presence of the drug.

If the person decides to stop taking the drug, the brain will fail to produce or trigger the high levels of pleasure or feel-good signals it was once accustomed to with the increased stimulation of the heroin. This can lead to symptoms of depression as the brain struggles to adjust.

Untreated depression can become worse or interfere with recovery efforts as a person detoxes. Research shows that heroin users who also suffer from depression have a greater risk of overdose and suicide.

Signs of depression:

  • Low mood without reason
  • Irritability
  • Sleep problems
  • Change in appetite
  • Weight gain or loss
  • Extreme fatigue
  • Feelings of worthlessness and guilt
  • Trouble concentrating
  • Slowed or accelerated movements
  • Feelings of hopelessness
  • Lack of enjoyment in usual activities or hobbies
  • Repeated thoughts of suicide or death

The important thing to remember is that the mood disorder depression is not the same as the depression of the central nervous system; not all drugs with depressant properties are classified as depressant drugs.

If you’re facing a heroin use disorder or depression, help is available for both. Do not wait to seek treatment: both of these disorders can lead to severe health consequences. With treatment centers across the country, The Recovery Village can help you find effective treatment options for your mental health and substance abuse issues. To learn more about how treatment can help you heal, contact a representative at The Recovery Village today.

Melissa Carmona
Editor – Melissa Carmona
Melissa Carmona puts years of writing and editing experience to work helping people understand substance abuse, addiction and mental health disorders. Read more
Jessica Pyhtila
Medically Reviewed By – Dr. Jessica Pyhtila, PharmD
Dr. Jessica Pyhtila is a Clinical Pharmacy Specialist based in Baltimore, Maryland with practice sites in inpatient palliative care and outpatient primary care at the Department of Veteran Affairs. Read more

U.S. Department of Justice, Drug Enforcement Administration. “Drugs of Abuse.” April 2020. Accessed July 3, 2021.

Department of Health, State Government of Victoria, Australia. “Heroin.” BetterHealth, June 23, 2017. Accessed July 3, 2021.

National Institute on Drug Abuse. “What are prescription CNS depressants?” March 2018. Accessed July 3, 2021.

National Institute on Drug Abuse. “Prescription Opioids and Heroin Research Report.” January 2018. Accessed July 3, 2021.

National Institute on Drug Abuse. “What is Heroin?” June 2021. Accessed July 3, 2021.

Martins, SS’; Fenton, MC; Keyes, KM; et al. “Mood and anxiety disorders and their ass[…]d Related Conditions.” Psychological Medicine, June 2012. Accessed July 3, 2021.

State of Hawaii Department of Health. “Risk Factors.” Accessed July 3, 2021.

National Institute of Mental Health. “Depression.” 2021. Accessed July 3, 2021.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.