Opiate painkillers

Opiate painkillers are medicines used to treat moderate to severe pain. They work by blocking pain signals to the brain and slowing down the body’s responses.

When used exactly as prescribed, opiate painkillers can be effective and safe. However, they carry risks, especially if used for long periods, in high doses, or obtained from illegal or unreliable sources.

Names you might hear

Opiate painkillers may be referred to by brand names, generic names or slang. In the UK and North West, common names include:

  • Codeine

  • Dihydrocodeine (DHC)

  • Tramadol

  • Morphine

  • Oxycodone

  • Fentanyl (medical patches)

  • Painkillers

  • Opiates

Some people may also refer to them as:

  • Pills

  • Codeine linctus

  • Lean (when codeine cough syrup is misused)

What do opiate painkillers look like?

Opiate painkillers come in many forms, including:

  • Tablets or capsules

  • Syrups or liquids

  • Injectable solutions

  • Skin patches

  • Lozenges, nasal sprays or suppositories

They can vary in colour, shape and strength depending on the medication.

How do people use opiate painkillers?

Opiate painkillers may be:

  • Swallowed

  • Sucked or dissolved

  • Snorted

  • Injected

  • Absorbed through the skin using patches

Most opiate painkillers are prescription-only medicines. Some low-dose opiates, such as codeine, can be bought over the counter, but should not be used for more than a few days without medical advice.

Injecting opiate painkillers is particularly dangerous and can cause severe damage to veins and arteries.

How opiate painkillers can make you feel

The effects depend on the drug and dose, but opiate painkillers may:

  • Reduce pain

  • Make you feel relaxed or calm

  • Cause drowsiness or sleepiness

Some people also experience:

  • Nausea or vomiting

  • Itching

  • Dizziness or light-headedness

At higher doses, opiate painkillers can dangerously slow breathing.

How long the effects last

How long opiate painkillers last depends on:

  • The type of medication

  • The dose taken

  • Your body size and tolerance

  • Whether other substances are used

Some last a few hours, while others can last much longer.

Physical health risks

Prescription opiate painkillers are tightly controlled to ensure dose and strength are predictable. However, risks increase if:

  • They are taken in higher doses than prescribed

  • They are used for long periods

  • They are bought illegally

Risks can include:

  • Constipation

  • Nausea and vomiting

  • Lethargy or extreme tiredness

  • Dizziness or fainting

In overdose, opiate painkillers can:

  • Suppress breathing

  • Cause loss of consciousness

  • Lead to respiratory arrest and death

Codeine-based products

Overusing products that contain codeine combined with paracetamol, aspirin or ibuprofen can cause:

  • Liver failure

  • Kidney failure

  • Severe stomach bleeding

  • Death

These risks can occur even though these medicines may seem harmless at normal doses.

Pregnancy and opiate painkillers

Regular use of high doses during pregnancy can lead to withdrawal symptoms in newborn babies.

Stopping suddenly without medical advice can increase the risk of miscarriage or premature labour. Pregnant women using opiates regularly should always seek medical advice before stopping.

Risks from injecting

Injecting any opiate painkiller can cause:

  • Severe vein and artery damage

  • Blood clots

  • Abscesses and infections

  • Gangrene

Sharing injecting equipment increases the risk of blood-borne viruses such as hepatitis C and HIV.

What opiate painkillers may be mixed with

If opiate painkillers are prescribed or bought legally from a pharmacy, their contents and dose are known.

Illegally sourced opiate painkillers may:

  • Be counterfeit

  • Contain unexpected substances

  • Be much stronger or weaker than expected

This increases the risk of overdose.

Mixing opiate painkillers with other substances

Mixing drugs always increases risk.

Mixing opiate painkillers with:

  • Alcohol

  • Benzodiazepines such as diazepam or Xanax

  • Other sedative drugs

greatly increases the risk of overdose, coma and death.

Dependence and withdrawal

All opiate painkillers can be addictive.

With regular use, people may develop:

  • Cravings

  • Tolerance, needing more to get the same effect

  • Physical dependence

Withdrawal symptoms can include:

  • Anxiety and restlessness

  • Sweating and yawning

  • Muscle aches and cramps

  • Nausea and diarrhoea

  • Sleep problems

Withdrawal can be very uncomfortable but support can help make it safer and more manageable.

The law

Strong opiate painkillers are controlled under the Misuse of Drugs Act and are usually Class A or B drugs.

Unless prescribed to you:

  • It is illegal to possess opiate painkillers

  • It is illegal to give them to someone else

  • It is illegal to sell them

Penalties can include community orders, prison sentences and unlimited fines, depending on the substance and circumstances.

Driving while under the influence of opiates is illegal and dangerous.

Staying safer

If someone is using opiate painkillers:

  • Follow medical advice and prescribed doses

  • Avoid mixing with alcohol or other drugs

  • Avoid injecting

  • Seek help early if use is becoming hard to control

If someone is very drowsy, unconscious, or breathing slowly, call 999 immediately. Seeking medical help will not get you into trouble.

Support from Wirral Ways

Wirral Ways offers free, confidential support for people affected by opiate painkiller use, as well as support for families and carers.

We can help with:

  • One-to-one support

  • Support to reduce or stop safely

  • Harm reduction advice

  • Mental and physical health support

  • Support with housing, benefits and wider wellbeing

Support is tailored to you and your goals.

Worried about someone else?

If you are worried about a friend or family member, you can contact us for advice and support. You do not have to manage this alone.

Get support

You can contact Wirral Ways to access support:

  • Self-refer online

  • Speak to a member of our team

  • Visit one of our services

Support is available, and help is there when you’re ready.

Last Updated on 4 February 2026