What are Opioid Painkillers?

In the last year, UK doctors wrote around 50 million opioid prescriptions and there has been a huge increase in opioid prescriptions being issued over the last decade – around 35%. Around 115,000 opioid prescriptions are written each day and – staggeringly – 5% of these lead to a death. The country has also seen overdoses increase to 12,000 a year (a rise of 87%) and deaths related to opioid use are around 2,000 (an increase of 47%). According to the Office for National Statistics, opioids like morphine and heroin are the most frequent substances mentioned on death certificates.

So, what are opioid painkillers and why are they so problematic? We’ll explore everything you need to know in this article.

What are opioid painkillers?

Opioid painkillers are a large group of medicines whose main use is for the treatment of pain. These drugs include natural chemicals like codeine and morphine along with other synthetic drugs. The World Health Organization mentions methadone, morphine and codeine as essential medicines to treat pain, especially for end-of-life care. Opioids like buprenorphine and methadone are also used as addiction treatments as they are not as strong.

Overall, there are over twenty opioids authorised in the UK for pain treatment. Their potencies all differ.

Naturally-derived opioids (opiates – from opium) include:

• Thebaine.
• Codeine.
• Morphine.

Synthetic opioids include:

• Tramadol.
• Fentanyl.
• Oxycodone.
• Pethidine.
• Methadone.

Heroin is an ester of morphine. It is more natural than synthetic opioids and is, therefore, considered to be an opiate.

The majority of opioid painkillers are only available on prescription, but you can find low-dose opiates like codeine available over the counter in combined medications used to treat mild to moderate pain.

Opioids are used to treat moderate to severe pain caused by the likes of broken bones, acute back pain and cancer, for example.

Can opioid painkillers be addictive?

Though these medicines are essential for pain relief, we must also remember that they are addictive and can be dangerous. Opioid painkillers are good for short-term pain relief for non-cancer pain. You’ll typically be prescribed them for less than three months.

Patients often find that their treatment is becoming less effective as time goes on. This is because they develop a tolerance to the drug and need an increased dose to provide the same pain relief they initially had when starting the drug. A developed tolerance is the first step towards dependence and addiction.

There are lots of risk factors involved in the development of an addiction, for example, mental health problems or a past history of substance misuse – including alcohol.

Signs of addiction include:

• Drug cravings even when there are adverse effects on health.
• Expressing a need for more or also using other painkillers.
• Taking the medicine for other reasons and not just for pain relief.
• Experiencing side effects from withdrawal.

What are opioid painkillers used for?

Opioid painkillers are usually prescribed to relieve acute pain, but they’re also given to cancer patients receiving palliative care and end-of-life care. They might be prescribed for post-operative pain, musculoskeletal disorders, post-infarction pain, or trauma. They are also used as substitutes for stronger opioids and drug addition to aid the detoxification process.

Examples of conditions where patients might be prescribed opioid painkillers:

• Acute pain following surgery.
• Trauma – Dislocation of joints, bone breakages, severe injuries, burns.
• Terminal cancer.
• Degenerative conditions like rheumatoid arthritis.

Opioid painkillers for cancer

Many cancer patients will be prescribed opioid painkillers as a part of their treatment plan. The type you have will depend on the severity of the pain. When taking opioid painkillers for cancer pain, the risk of addiction is considered to be less. However, dependence is common.

Unlike opioid addicts, cancer patients are more likely to be physically dependent on the drugs rather than psychologically dependent. This is because they usually don’t experience a ‘high’ because their pain is so great. Physical dependence, unlike addiction, is typically temporary and with gradual withdrawal, will fade.

How are opioid painkillers abused?

Even short-term opioid use can lead to abuse, addiction and overdose. Anyone can develop an opioid addiction if they take an opioid painkiller. A person’s history and how long they use the drug do play a role in opioid abuse, but it isn’t possible to know who is vulnerable.

Whether they’re used legally or illegally, opioid painkillers are the main contributing factor to overdose deaths.

Opioid addiction is a serious problem. Something which once provided relief and was pleasurable becomes a substance that the person cannot live without. The patient will have irresistible cravings and will go to extreme lengths to source more no matter how harmful the consequences are.

These highly addictive substances are problematic because they activate the brain’s powerful reward centres and trigger endorphins to be released. While muffling pain perception, they also boost pleasurable feelings and create a strong feeling of well-being. When these feelings wear off, the person often wants them back as quickly as possible.

The risk of developing severe depression is 38% higher among those who abuse opioid painkillers.

How do opioid painkillers affect the body?

There are two main ways in which opioid painkillers work. They affect the nerve receptors in the brain and also influence how it functions. These drugs attach to the nerve receptors to block pain transmission. This limits how much pain a person feels. They mainly attach to the nerve receptors in the intestines and spine as well as other organs, which is why they’re good at stopping pain.

Besides this, they also change the chemistry in the brain. So, if they haven’t blocked all pain, the remaining pain you feel will be experienced differently, which is why lots of people feel euphoric when they take opioid painkillers.

However, there are negative effects too (and not just addiction). Opioid painkillers interfere with how the nervous system works. Of course, this is advantageous for managing pain, but it can be problematic if it affects organs.

What are the risks of opioid painkillers?

Treating pain with opioids can lead to a lot of side effects. These include anxiety, depression, hyperalgesia, headache, coma, and death.

They can also cause dangerous sedation and severe constipation. It’s easy for a person taking opioid painkillers to become confused and cognitively impaired. An accidental overdose can easily happen. All it takes is for someone to hoard an extra pill or two or to take more in the hope of a better night’s sleep and it becomes extremely dangerous.

Combining opioid painkillers with other drugs, including alcohol, is profoundly serious indeed and can be deadly.

When you take a low dose of an opioid painkiller, you might feel tired and sleepy. However, a high dose might go even further and slow your heart rate and breathing rate right down. Ultimately, this can be fatal.

Opioid painkillers mixed with other substances

Lots of people who take opioids will also take other drugs. This might be because they’re looking for that boost they felt initially or because they’re unaware of how serious this is. Taking other drugs alongside opioids might even mask overdose symptoms, which is dangerous.

By their nature, opioids are depressants. This means that they slow down central nervous system activity. This is the opposite of stimulants, which speed things up. If you mix opioids with a stimulant, it can cause the organs to be strained. So, while an opioid painkiller will slow down your breathing and heart rate, an ‘upper’ will do the opposite. This means overdoses can be masked and so treatment might be delayed.

Mixing stimulants with opioids is known to cause:

• Respiratory failure.
• Seizures.
• Cognitive impairment.
• Heart failure.
• Stroke.
• Cardiac arrest.
• Sudden death.

Besides these medical issues, mixing the two can also increase a person’s risk of:

• High drug tolerance.
• Psychological addiction.
• Severe drug dependence.
• Serious accidents (injuries, vehicle crashes, falls, etc.).
• Mental health problems.
• Suicide attempts.
• Violent or aggressive behaviour.
• HIV exposure (from needles).
• Foetal drug exposure in pregnancy.

Short-term and long-term effects of opioid painkillers

When a person takes opioid painkillers, the effects are almost instant. This is particularly true for those who have never or rarely taken opioids.

In terms of short-term effects, these include:

• Respiratory depression.
• Nausea.
• Drowsiness.
• Paranoia.
• Lethargy.

Due to these side effects, patients are advised not to use heavy machinery or drive. In fact, anything that takes a moderate amount of mental or physical effort is not recommended.

Opioid painkillers can make a person feel relaxed. This is often why people abuse these drugs, rather than because of pain.

Long-term effects

Continuing to use opioids (or abuse them) often results in increased tolerance, physical dependence and, ultimately, addiction. As such, the long-term side effects of using opioids are life-threatening and frightening.

With an increased tolerance, dependence or addiction, there are serious side effects.

These include:

• Nausea.
• Vomiting.
• Bloating and abdominal distention.
• Liver damage.
• Immune system suppression.
• Brain damage.
• Coma.
• Death.

Opioid painkillers depress the CNS (central nervous system). This regulates bodily functions like your heart rate and breathing. As such, a high dose of opioids can slow your breathing to dangerous levels or stop it altogether. When hypoxia happens, the blood flow can be cut off to the brain, which causes neurological and psychological effects. This might mean temporary or permanent brain damage, coma, or death.

Using opioids for a long period of time can also lead to problems with motor skills. In turn, this causes an increased risk of injuries and falls.

If opioid painkillers are administered by injection (not in a medical setting), there are other long-term side effects, including:

• Heart infections.
• Heart problems.
• Blood infections.
• Hepatitis.
• Skin infections, e.g., gangrene.
• HIV.

Lots of these diseases and infections are caused by using a dirty needle. Those who inject opioids are much more at risk of getting blood-borne illnesses and HIV compared to those who take the drug in another way.

Even when a person stops taking the drug, cravings as well as anxiety and depression often continue for months or years.

What are the different forms of opioid painkillers?

There are many different forms of opioid painkillers and patients will be given the drug in different ways, depending on the reasons for taking the drug.

Common ways opioid painkillers are prescribed include:

• Tablets.
• Liquids.
• Nasal sprays.
• Skin patches.
• Suppositories.
• A dissolvable tablet placed under the tongue.
• A syringe driver.
• An implanted pump.
• Injection.

As well as the different ways of taking the drug, there are different opioids in terms of strength and speed of release.

Weak opioids

These include tramadol, dihydrocodeine, and codeine. Patients are often given a weak opioid if they can’t control their pain by NSAIDs or paracetamol. Examples of situations where weaker opioids might be prescribed are post-operative care, including caesarean section deliveries.

Stronger opioids

If a weaker opioid painkiller doesn’t control a person’s pain, they might be given a stronger option. This will usually begin as a low dose, which can then be increased. Stronger opioid painkillers include fentanyl, morphine, oxycodone, buprenorphine, tapentadol, and methadone.

You can often get these stronger opioids at different release speeds.

These are referred to as:

• Fast-acting opioid painkillers (or ‘immediate release’).
• Long-acting opioid painkillers (or ‘slow/modified release’).

Fast-acting, immediate-release opioids

These opioid painkillers will start to take effect after around 20 minutes and their full effect will be felt within an hour. This makes these drugs ideal for treating pain changes and breakthrough pain. Lots of people start off with fast-acting opioids, particularly after trauma.

Long-acting, slow/modified-release opioids

Patients usually take long-acting, modified-release opioid painkillers to control their background pain twice per day. These drugs take a longer time to reach their full effect, which means missing a dose can be problematic. For them to work properly, it’s important to take them at the same time each day. Occasionally, people will take a slow-release dose and an immediate-release dose at the same time in order to feel initial relief as well as the effects of the longer-acting painkiller.

Final thoughts

Though opioid painkillers are addictive and their long-term use problematic, they are excellent for the control of acute pain and long-term pain from cancer. It’s important to follow the instructions carefully to avoid unnecessary side effects and avoid tolerance, dependence and addiction. Abusing opioid painkillers is serious and can lead to many health problems, including death.