How Heroin Works

Clear Treatment

Where does heroin come from?

Heroin originates from opium poppies, but not directly. As opium poppies flower, the seed pods fill with codeine- and morphine-rich sap. About one week later, the encapsulated sap ripens and is then ready to be extracted. The extraction process typically begins in late afternoon, and is usually accomplished by vertically cutting the exterior side walls of the seed pods. This technique enables the sap to seep out overnight without drying or coagulating.

As the sap seeps out it comes in contact with oxygen, which turns its color from white to pink to dark brown. The following morning the sap should be brown to black in color, which indicates that it’s ready to be harvested. After harvesting it’s cleaned and dried, and made into “Opium.” Most opium is about 10-14 percent morphine by weight. In places like Afghanistan and Mexico, where the drug trade thrives, morphine is mixed with acetic anhydride and boiled to make heroin.

Personality Traits of Heroin Addicts


Facts about heroin

Heroin is typically injected into a vein or muscle, but it may also be snorted or smoked. When injected it delivers a unique “flash sensation,” like a surge of warmth, followed by relaxation and contentment. Yet, in just a few short hours these effects wear off and the user develops a strong urge to do it again. This urge is one of the reasons why heroin is considered the most addictive drug in human history.


Hazards of intravenous heroin use

Sharing used needles may result in HIV/AIDS or hepatitis C (HCV). Men and women can also get these diseases by having unsafe sex. Sometimes heroin users forget to use condoms simply because they’re high.


Heroin effects on the brain

Regardless if a heroin user sniffs it, smokes it or injects it, as it permeates the brain it attaches to tiny proteins atop nerve cells called receptors. Scientists have found three receptors that respond to heroin: mu (μ)kappa (κ) and delta (δ). These receptors are called opioid receptors and each type plays a different role. Since mu (μ)kappa (κ) and delta (δ) receptors are the first known opioid receptors, they are commonly referred to as the classical opioid receptors.

  1. mu (μ) opioid receptors (MOR) – the mu receptor is the main “heroin receptor.” Throughout the body these are the most abundant opioid receptors and they’re directly responsible for heroins’ pleasurable effects, acute pain relief, physical dependence and addiction, but also sedation, respiratory depression, slow heart rate, nausea and vomiting as well as reduced gastrointestinal motility.
  2. kappa (κ) opioid receptors (KOR) – the kappa receptor is responsible for heroin’s anxiolytic effects, trance-like states, physical dependence, and addiction, but also spinal analgesia, and dysphoria (in some).
  3. delta (δ) opioid receptors (DOR) – the delta receptor is responsible for heroin’s relief from persistent pain, reduced gastrointestinal motility and modulation of mood.


Actions of heroin

Heroin is an extraordinary drug because it binds to and activates μ-mu opioid receptors, which are the most prevalent and powerful opioid receptors in the brain and body, and the receptors most responsible for heroin’s effects.

  • Euphoria
  • Pain relief
  • Sedation
  • Respiratory depression
  • Constipation
  • Cough suppression


Limbic System, Brainstem, Spinal Cord

Heroin’s effects not only depend upon which type of opioid receptor it activates, but also the area of the nervous system in which they’re activated. Three of the most affected areas are the limbic system, which is in the forebrain; the brainstem, which is the bottom-most portion of the brain; and the spinal cord, which is a thin tube of nerves that extends from the base of the brainstem downward. These areas are not the only places you’ll find opioid receptors, but they have the most opioid receptors, and also produce the greatest effects.

heroin effects on the brain


  • Limbic System – When heroin attaches to opioid receptors within the limbic system it creates feelings of pleasure, relaxation, and contentment.
  • Brainstem – Underneath the limbic system is the brainstem. It connects the forebrain with the spinal cord. When heroin attaches to opioid receptors in the brain stem it slows breathing, inhibits coughing, and reduces pain.
  • Spinal Cord – When heroin attaches to opioid receptors within the spinal cord it reduces pain.


Lack of Concentration

One of the telltale signs of heroin use is an inability to concentrate. Let’s say you’re talking to a heroin user, and the heroin user is listening to you. You’ll likely see the user’s eyelids start to droop. He or she may even fall asleep as your talking. The sleep effect is colloquially called “nodding out.” It occurs because heroin sedates the brain. If a large dose is used it can cause unconsciousness, but if too much is used it can lead to coma or death.


Heroin effects on the body


Heroin does some strange things to your body. It makes your pupils smaller, your skin itchy, and your stomach nauseous. It’s also a powerful sedative. Consequently, the great danger is vomiting while you’re asleep.


Pinpoint pupils and itchiness are two of heroin’s most obvious signs that a person is using heroin. If you look closely at a heroin user’s eyes you’ll notice two very small pupils, even when indoors. Heroin addicts use the term “pinned” as in “you’re pinned, he’s pinned, she’s pinned,” to acknowledge that someone is high on heroin. You may also notice that heroin addicts have a tendency to scratch their nose. In fact, itchiness is so common among heroin addicts that they often joke about it.


One of heroin’s worst after effects is constipation. This problem often leads to hemorrhoids. Constipation develops because heroin slows down the transit time of food. Motility is slowed because of delayed gastric emptying of the stomach, reduced peristalsis, and decreased gastrointestinal secretions. The result is hard stools.

Colon Cancer

The potential hazard of chronic constipation (hard stools) is colorectal cancer, which is one of the most common cancers, having a deep impact on the health of society. One of the most important findings is that opiate abusers with colorectal cancer have a much higher rate of mortality as compared to the general population, 25% vs 10% respectively.1, The hypothesis being that opiate abusers do not notice the symptoms of colorectal cancer, until the cancer is much further along. Delay in seeking a medical examination is primarily attributed to opiates being painkillers, so they don’t notice it. But also because users grow accustomed to chronic constipation and discharging blood, i.e. it’s not that big of a deal as compared to opiate withdrawal, which is their primary problem.


Heroin Overdose

Signs of a heroin overdose are pinpoint pupils, slowed or stopped breathing, blue lips and fingernails, cold clammy skin, and seizures.

You may stop breathing

People generally overdose on heroin because they can’t tell, with any certainty, what dose is safe. What’s more…even a tiny overdose can be fatal. Injecting heroin is the most dangerous method of heroin administration. It’s dangerous because it gets the most heroin to the brain, the quickest way possible. As soon as heroin gets into the brain it quickly suppresses breathing, which causes a rapid drop in oxygen saturation. If breathing slows too much or stops altogether, the cells in the brain become deprived of oxygen and begin to die. That’s why even a tiny heroin overdose can kill you.


Heroin Dependence

Dependence to heroin is a medical condition whereby withdrawal symptoms develop whenever the addict stops using. When a heroin addict tries to quit, they develop pain in their muscles and bones, get the chills, throw up, and feel weak. The response to withdrawal is a very strong urge to take the drug again, basically to feel better. In reality, the heroin addict lifestyle is a never-ending journey of overcoming the negative effects of withdrawal.


Heroin is a prodrug

Heroin is possibly the perfect drug for manifesting drug addiction. Ironically, we know now that heroin is actually a prodrug, and as such, does not get anyone high.

What is a prodrug?

A prodrug is a drug that, after administration, converts into another drug. In other words, what heroin turns into, is what gets the heroin user high – not the heroin itself. We know this to be true, because there has never been a fatal heroin overdose victim who was found, during the autopsy, to have any trace of heroin inside their brain. NEVER!

Being a prodrug, is also the reason why drug screenings never test for heroin. NEVER!

The heroin conversion

Heroin (diacetylmorphine) converts into 6-monoacetylmorphine (6MAM).

Read More on Heroin Is A Prodrug…


Metabolites of Heroin

After heroin is administered it starts traveling through the circulatory system. As soon as heroin mixes with blood it begins to spontaneously metabolize into 6-MAM. Furthermore, 6MAM metabolizes into morphine, and morphine metabolizes into M6G, and M6G into another chemical and so on and so forth. These newly metabolized chemicals are classified as either active metabolites or inactive metabolites. Active metabolites produce drug effects and inactive metabolites do not. The top-two active metabolites of heroin are 6-monoacetylmorphine (6MAM) and morphine. Since morphine is the longest lasting metabolite of heroin, drug screenings test for it.


Cause of heroin addiction

The likelihood that a drug will lead to addiction is linked to the speed with which that drug promotes dopamine, the intensity of dopamine effects and the reliability that dopamine effects will occur.

Opiates like heroin, morphine and oxycodone are fast acting, produce a lot of dopamine and work close to 100% of the time. That’s why these three opiates in particular have been linked to several opiate addiction epidemics. The U.S. is currently coming out of an oxycodone epidemic and we’re currently in another heroin epidemic. The only morphine epidemic began during the Civil War and was quickly supplanted by heroin at the beginning of the 20th century.



Neurotransmitters are chemicals within the nervous system that communicate information throughout our brain and body.  They send signals from one neuron to another neuron.  The brain uses neurotransmitters to tell your lungs to breathe, your heart to beat, and your stomach to digest.  They also affect your mood, focus, and motivation.

Endorphins are the body’s natural neurotransmitters and they typically reduce pain or modulate mood. All addictive drugs mimic the actions of some neurotransmitter; in the case of heroin that neurotransmitter is probably endorphin. Ironically, the word “endorphin” is short for endogenous morphine, which means morphine made from within the body.


How heroin increases pleasure?

What typically happens is that 6MAM and a little morphine bind to and activate more mukappa and delta opioid receptors than any naturally occurring event. Therefore, heroin use ultimately results in a massive amplification of dopamine activity, which produces intense pleasure.

The sequence of events, from heroin use to feeling good, is quite simple. Heroin turns into 6MAM and a little morphine via the blood and liver, respectively.  6MAM and a little morphine enter the brain and behave like neurotransmitters and activate opioid receptors in the Ventral Tegmental Area (VTA). These activated receptors inhibit the release of GABA. Less GABA stimulates the release of dopamine. Dopamine travels from the VTA to the nucleus accumbens (NAc). Dopamine in the NAc attach to Dopamine receptors (D2) and the post-synaptic response is pleasure.


Does Heroin Affect Sex Dive



Neurons and Interneurons

What we’re looking at here are neurons. Your average neuron consists of a cell body, an axon and dendrites. The left picture shows a GABA axon terminal on top and a Dopamine dendrite on the bottom. The right picture shows a Dopamine axon terminal on top and an unspecified dendrite on the bottom. The space in between one neuron and the other is called a synapse. That is where signals from one neuron pass to another. Since the two neurons are not connected, the neuron on the top must release chemicals (neurotransmitters) from little vesicles (the bubbles in the picture) into the synapse.

Opioid Interneuron

This is where it gets interesting. Neurotransmitters have one of two possible functions, either to excite or inhibit a response. GABA neurotransmitters are considered inhibitory neurotransmitters. So after GABA neurotransmitters cross the synapse, they bump into and activate GABA receptors on Dopamine dendrites. The GABA receptors then send inhibitory signals to the Dopamine nucleus – to not release Dopamine. However, when heroin is consumed, the opposite occurs. But why does that happen?

The answer is absolutely fascinating. Heroin enters the body and quickly turns into 6-monoacetylmorphine (6MAM) and a little Morphine. Both 6MAM and Morphine bump into and activate opioid receptors on GABA neurons. Both 6MAM and Morphine act like inhibitory neurotransmitters themselves and suppress GABA neurons, to greater or lessor degree depending upon dosage. 6MAM and Morphine slow the rate of GABA release, which results in disinhibition of Dopamine. The left image up top shows inadequate GABA unable to completely suppress the release of Dopamine. The right image up top shows Dopamine traveling down the axon and into a different synapse, where it bumps into Dopamine receptors of a third neuron and around and around the brain it goes.


How long does heroin work?

6MAM has a short elimination half-life, which ranges between 6-25 minutes. Therefore, approximately 30 minutes after heroin is administered, over half of 6MAM molecules will have metabolized into heroin’s second metabolite, that is to say morphine. Morphine’s half-life is around 2.5 – 5 hours. Heroin’s half-life is considered the total of these two, and that means heroin’s half-life is a little less than 3 – 5.5 hours. The drug-effects of heroin last between one and two half-lives or 3 – 11 hours. The mean average being 7 hours.

Morphine activates opioid receptors longer than all other active metabolites of heroin. Therefore, the lingering drug effects are more connected to morphine, while the acute drug effects are more connected to 6MAM, but they do overlap.


Heroin adverse reactions

The most common adverse effects associated with the heroin use include nausea and vomiting, sedation, itchiness, urinary retention and constipation. Serious adverse effects frequently reported with heroin use include: respiratory depression, hypotension and delirium.

  1. Heroin Overdose: Excessive heroin consumption may cause the brain to forget to breath. This may result in “hypoxia,” a medical condition in which there’s not enough oxygen in the blood to sustain life.
  2. Heroin Tolerance: Needing more heroin to get the same intensity of effect.
  3. Heroin Dependence: Chronic heroin use causes physical dependence, which means that you are susceptible to withdrawal symptoms when you stop.
  4. Heroin Addiction: Heroin use can also lead to addiction, which is a tenacious drive to get and use heroin despite negative consequences. It’s estimated that almost 1 in 4 (approx. 23%) new heroin users will become addicted.
  5. Viruses: If you consider intravenous heroin use, then there are other health risks, such as contracting HIV, Hepatitis C, and Hepatitis B.


How does heroin affect the Gastrointestinal Tract

Heroin depresses brain centers that control major muscle groups. These muscles groups respond by slowing down the rate and depth of respiration, inhibiting coughs, and slowing down gastrointestinal motility. Heroin works in the GI Tract by reducing peristalsis, decreasing gastrointestinal secretions and relaxing longitudinal muscle in the colon as well as simultaneously/increasing contractions of the anal, esophageal and other sphincter muscles.

1.Heroin works by inhibiting lower esophageal sphincter relaxation, which causes abdominal cramping.

2. Heroin works by contracting the gallbladder, which delays gastric emptying, and that can result in abdominal discomfort.

3. Heroin works by increasing acid release and delaying gastric emptying of the stomach, which results in nausea, vomiting and abdominal cramping.

4. Heroin works by slowing transit time of food, which results in constipation, bloating and cramping.

5. Heroin works by increasing anal sphincter tone (contracts sphincter), which results in constipation.


Long-term Effects of Heroin

Chronic heroin use changes your brain. Scientific studies have shown that heroin use can deteriorate your brain’s White Matter, which may impair your decision-making abilities. The evidence also suggests that duration-of-heroin-use was the primary factor in White Matter injury.2, 3

We know now that heroin use creates long-term imbalances in your nervous and endocrine systems that are not easily reversed. Some of these changes are primary factors that lead to heroin dependence and heroin withdrawal. Furthermore, once you become an addict, seeking and using heroin becomes your primary purpose in life.


Treatment for heroin dependence

The following treatment options are typical heroin addiction recovery strategies.

  • Heroin Detoxification: Detox generally lasts about a week and includes medications like Suboxone that suppress withdrawal symptoms
  • Primary Care: 30-days or less residential treatment that generally combines behavioral and cognitive therapy.
  • Long-term Care: 31-days or longer residential or outpatient treatment services that generally combines treatment and recovery planning.


Heroin is a Narcotic

Heroin is a narcotic. A narcotic is a drug that produces narcosis. Narcosis means it makes you sleepy. Depending upon how much heroin you take, determines how much of a narcotic effect will occur. There are other factors as well, such as how long you’ve been using heroin, i.e. tolerance, and how you administer it. In general, heroin is taken in large doses, but regardless of how much you take and how long you’ve been taking it, if heroin is injected, it acts faster and more intensely.

The euphoric, analgesic, sedative and respiratory effects of heroin are well known. However, sedation and respiratory depression are two of the most serious problems. There is another factor that’s often overlooked. That heroin kills people, and not just by overdose. Some heroin users fall down and hit their head, others crash into telephone poles, and some commit murder in support of their habit.



1. Relation Between Opiate Abuse and Colorectal Cancer Prognosis, 2015

2. White matter impairment in chronic heroin dependence: a quantitative DTI study. Brain Res 1531:58-64, 2013

3. Progressive White Matter Microstructure Damage in Male Chronic Heroin Dependent Individuals, 2013