Opioid

Opioids are a group of drugs that come from or act like substances found in the opium poppy plant. They work on special parts of the brain and body called opioid receptors to help relieve pain.

Doctors use these drugs to manage pain, for example during surgeries. They are also used for other reasons, such as stopping severe diarrhea, treating dependence on opioids, and stopping cough.

However, opioids can be dangerous. They can cause side effects like itching, feeling sleepy, feeling sick, and trouble breathing. Long-term use can make it very hard to stop taking the drug. Because of these risks, most opioids are closely watched and regulated.

Terminology

Opioids are drugs that come from or act like substances found in the opium poppy plant. They help with pain and include natural drugs like morphine, as well as man-made ones like hydrocodone, oxycodone, and fentanyl. Some opioids can block the effects of others, like naloxone. The word "opiate" is an older term for opioids that come from opium. Sometimes, people use the word "narcotic" to mean opioid, but this word can have negative meanings and is not always the best choice.

Medical uses

Opioids are medicines that help to ease pain. They are often used for short-term pain, like after surgery, because they work quickly. They can also help people with serious, ongoing pain from conditions such as cancer. However, using opioids for a long time can have risks, so doctors are careful when prescribing them.

Opioids are sometimes used for other purposes, like stopping a cough or controlling certain stomach problems, but they are not always the best choice. For example, they are not recommended for children with a cough. Doctors also use opioids to help with breathing problems in very serious illnesses. But, it’s important to remember that using opioids for a long time can sometimes make pain feel worse instead of better.

Adverse effects

Opioids can cause many different effects in the body. Some common ones include itching, nausea, vomiting, constipation, drowsiness, and dry mouth. Others include dizziness, loss of appetite, and slowed breathing.

Long-term use of opioids can lead to dependence, where the body gets used to the medication. This means that stopping suddenly can cause withdrawal symptoms. Some people may also build tolerance, needing higher doses over time to get the same effect.

Using opioids can affect work and daily activities, especially for tasks that need full attention, like driving or operating heavy machinery. It’s important to use opioids carefully and follow a doctor’s guidance.

Interactions

Doctors who give opioids to patients with other medicines need to be careful. Mixing opioids with some medicines can be very dangerous.

When opioids are taken with medicines that slow down the body, like some sleeping pills or alcohol, it can cause serious problems, such as stopping breathing. Doctors can help by watching patients closely and changing treatment when needed.

There are special medicines called opioid antagonists, such as naloxone or naltrexone, that can stop the strong effects of opioids. These medicines work by blocking the parts of the body that opioids affect. They are helpful if someone has taken too much opioid and needs emergency care. But using these medicines needs careful planning to keep the person safe while still helping with pain.

Pharmacology

See also: Opioid receptor

Opioids connect to special places in the body called opioid receptors. These receptors are found in the nervous system and other parts of the body. There are three main types of opioid receptors: μ, κ, and δ. These receptors help control pain and other body functions.

When an opioid connects to a receptor, it can do different things in the body. For example, the drug morphine helps with pain, but it can also cause breathing problems. Each opioid works in its own way, which is why there are many different opioids.

Functional selectivity

Scientists are trying to design new drugs that help with pain but have fewer side effects. This idea is called functional selectivity or biased agonism. One example is a drug called oliceridine.

Opioid comparison

Main article: Equianalgesic

Researchers have studied how strong different opioids are. They use tables called equianalgesic tables to help doctors choose the right opioid and dose for patients.

Usage

In the 1990s, doctors began prescribing opioids more often. These medicines were first used for severe pain, like from cancer, but are now also given for long-term pain. This has caused many people to become addicted, and some have died from taking too much. The United States and Canada use more of these medicines than many other places. Some groups, like First World communities and people with less money, have been especially affected. Experts say this may be because other ways to manage long-term pain are not always available or too expensive. While opioids can help with pain, it's important to think about the risks. Efforts are being made to reduce the use of these medicines.

International Narcotics Control Board First World opioid epidemic opioid tapering

History

Naturally occurring opioids

Opioids are some of the oldest drugs known to people. The earliest signs of the opium poppy go back to around 5,700–5,500 BCE. Seeds from this plant have been found in places like the Iberian Peninsula and the Italian Peninsula.

People have used the opium poppy for thousands of years for healing, enjoyment, and spiritual reasons. Ancient writings from places like Sumer mention its use. The Egyptians wrote about it to help soothe children and treat infections. The Greeks, including Hippocrates, valued it for helping people sleep and easing pain.

Laudanum

In the past, the word "laudanum" was used for many useful medicines. Later, it came to mean a mix of opium and alcohol. One famous recipe from the 1600s mixed opium with wine and spices. This mixture was used for many years in Europe and the Americas. Other opium-based medicines included Paregoric for children, Black-drop for stronger needs, and Dover’s powder.

The opium trade

Opium became a big part of trade between many countries. The British East India Company started selling opium from India in the 1700s. This trade led to conflicts, including wars between China and Britain over opium.

Morphine

In the 1800s, scientists made important discoveries about opioids. A German scientist named Friedrich Sertürner was the first to separate morphine from opium in 1804. Later, new ways to give medicine under the skin were developed, making it easier to give exact amounts of morphine.

At first, morphine was seen as a wonderful medicine for pain and helped people sleep. It was used during wars and for many health issues. But people later found that it could be habit-forming.

Codeine

Another opioid called codeine was discovered in 1832. It came from studying the leftovers of morphine processing. This discovery led to new medicines for coughing and diarrhea.

Semi-synthetic and synthetic opioids

In the 1900s, scientists created new types of opioids. Some of these were stronger than older ones. For example, heroin was made in 1874 but was stopped when its habit-forming nature was noticed. Other new opioids included oxycodone, hydrocodone, and fentanyl, which is much stronger than older opioids.

Criminalization and medical use

Laws were passed to control the use of opioids. In the United States, the Harrison Narcotics Tax Act of 1914 made non-medical use illegal. Later, guidelines were created to help doctors prescribe opioids safely for pain. In the 1990s, strong marketing led to more opioid use, which caused health problems. This led to new rules in 2016 to reduce opioid prescriptions.

Society and culture

The word "opioid" started in the 1950s. It comes from "opium" and ends in "-oid," meaning "like opiates." Opium comes from a special flower, and opiates are drugs like morphine made from it. Scientists found these drugs work by turning on tiny parts in our bodies called opioid receptors.

In the United States, leaders have tried to help people use these drugs safely. In 2017, the government said this was a big health emergency. Some places track who gets these drugs to make sure they are used safely. Doctors are encouraged to use the smallest amount needed and to avoid mixing these drugs with others that can be dangerous.

Some people use these drugs just to feel happy, even if they don’t need them. This can lead to serious problems. Many countries work to make sure people in pain can get the help they need, especially where these medicines are hard to find.

Veterinary use

In the 1600s, scientists first tested opium, a plant-based substance, on animals. They gave it to dogs and watched how it made them sleepy. Later, they found that different animals reacted in different ways. For example, cats and horses looked confused, while dogs lost consciousness.

Today, these substances help animals feel less pain. They can be given in different ways, such as under the skin or into a vein. Common options include morphine, fentanyl, and buprenorphine. There are strict rules for using these substances in farm animals to keep everyone safe.

Classification

There are several types of opioids:

• Natural opioids: These come from the opium poppy plant and include substances like morphine and codeine.
• Semi-synthetic opioids: These are made from natural opioids and include drugs like oxycodone and hydrocodone.
• Fully synthetic opioids: These are made entirely in a lab and include fentanyl and methadone.
• Endogenous opioids: These are natural pain-relieving chemicals that our bodies make, such as endorphins.

Opioids work by attaching to special receptors in the brain and other parts of the body to help reduce pain. Some opioids can also affect mood and energy levels.