Drug Tolerance: Differences Between Fentanyl And Heroin Tolerance

Heroin and Fentanyl are opioid drugs that act on opioid receptors in your brain to reduce pain and increase pleasure and relaxation. They are very strong, very fast-acting and can be fatal in as little as one dose.

Both have a different drug tolerance level. In this article, I will take you through the difference in the tolerance level of the drugs - Fentanyl and Heroin.

What Is Fentanyl?

Fentanyl is a synthetic opioid drug that has been approved by the US Food and Drug Administration (FDA) for pain relief and anesthetic use. It is about 100 times more powerful than morphine, and 50 times more powerful than heroin as pain relief.

The drug is known in a couple of names aka street names such as Apace, China Girl, China Town, Dance Fever, Friend, Goodfellas, Great Bear, He-Man, Jackpot, King Ivory, Murder 8, Poison and Tango & Cash.

What Is Heroin?

Heroin is a drug that has a high addictiveness and is a fast-acting opioid. It is made from morphine, which is a naturally occurring compound that is extracted from the seed pods of certain types of poppies grown in Mexico, South America and Southeast Asia, as well as in Afghanistan and Pakistan. Heroin is available in white powder form in Mexico and South America, and in black tar and brown powder form in Mexico.

The street names of Heroin are: Big H, Black Tar, Chiva, Hell Dust, Horse, Negra, Smack, and Thunder.

What Does Tolerance Mean In Drugs?

Drug Tolerance Definition: Tolerance is a reduced response to a drug. It occurs when a drug is taken repeatedly and the body becomes accustomed to the repeated use of the drug. For example, when someone takes large doses of morphine or alcohol over a long period of time, they need to take larger and larger doses to get the same effect. Tolerance usually develops because the metabolism of the drug accelerates (usually because the liver enzymes that metabolize the drug become more active) or because the number of receptors (cell receptors) to which the drug attaches to increases and the strength of the receptor-drug bond decreases. Tolerance is not related to addiction or dependence.

Differences Between Fentanyl And Heroin Drug Tolerance

While tolerance for drugs such as fentanyl and heroin increases with regular use, there are some differences in how tolerance is affected by these drugs.

The following are some of the most striking differences between the two most popular drugs - Heroin and Fentanyl.

Take a look!

1. Mechanism Of Action

• Fentanyl: Fentanyl is a synthetic opioid. It works by attaching to the body’s opioid receptors. These receptors are mainly located in the brain. When fentanyl binds to these receptors, it causes pain relief and euphoria.
• Heroin: Heroin is derived from morphine and is also a brain opioid that attaches to opioid receptors. The effects of heroin are similar to those of fentanyl but less powerful. The brain converts heroin into morphine, resulting in analgesia and euphoria.

2. Potency

• Fentanyl: Fentanyl has a much higher potency than heroin. Because fentanyl is so strong, people who use it may develop tolerance faster. As tolerance increases, people who use fentanyl will need to take higher doses to get the same amount of pain or euphoria. This may lead to a faster increase in dosage.

• Heroin: Although heroin is a strong opiate, it is much less potent than fentanyl. People develop tolerance to heroin, but usually at a much slower rate than they do to fentanyl.

3. Risk Of Overdose

• Fentanyl: Fentanyl has a very high overdose risk due to its high potency. Tolerance can cause people to look for higher doses, which increases the risk of accidental overdose as there is little difference between safe and deadly doses.

• Heroin: Heroin overdoses are also a serious problem, but due to the lower potency of heroin compared to fentanyl, your margin of error might be slightly wider. Tolerance can still push you to overdose and death.

4. Cross-Tolerance

Fentanyl and heroin both interact with opioid receptors in the same way. Because of their similar actions, it is likely that people with tolerance to one opioid will also have tolerance to another. However, due to the large difference in potency between the two, it is important to be cautious when switching between them to avoid overdose.

5. Medical Vs Illegal Use

• Fentanyl: It is mainly used in medical settings for acute pain management, usually for post-operative pain management, chronic pain management, or pain associated with cancer. Medical use is regulated and closely monitored to avoid overuse and abuse.

• Heroin: Heroin is used illegally for its psychoactive properties. Unlike other drugs, heroin does not have the same level of supervision and dosage control in a medical setting. As a result, heroin is used in an unregulated manner, which can result in quicker tolerance development, an increased risk of overdose and addiction.

Bottom Line

Drug tolerance is pretty subjective as different drugs have different tolerance levels. However, as assessed in the article, Fent or Fentanyl has a much higher tolerance level as compared to Heroin, which is also a strong opiate. People usually develop Fentanyl tolerance at a much higher rate while for Heroin, it is developed at a much slower rate. 

Fentanyl and heroin are both psychoactive substances/drugs that can cause physical dependence, addiction and withdrawal symptoms upon discontinuation of use. However, the potency of fentanyl increases the risk of tolerance to hazardous levels and can result in more serious consequences, such as fatal overdose.