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Substance Use InformationSupport without stigma · UK
Medicines

Prescription medicines

Medicines can be effective and safe when prescribed and reviewed — some can also cause dependence.

What is it?

Some prescribed medicines — including opioids, benzodiazepines, gabapentinoids and some sleeping tablets — can lead to tolerance and dependence. This can happen to people taking their medicine exactly as prescribed. It is not a personal failure.

Common forms

  • Tablets and capsules
  • Patches
  • Liquids
  • Injections

How it affects the body

Effects depend on the medicine. Sedating medicines slow the nervous system and can affect breathing, particularly in combination.

Short-term effects

  • Intended therapeutic effect
  • Drowsiness or dizziness with sedating medicines
  • Side effects that vary by medicine

Long-term effects

  • Tolerance and dependence with some medicines
  • Withdrawal effects if stopped abruptly
  • Interactions with other medicines and alcohol

Dependence and addiction

Dependence can develop when the body and brain adapt to regular use. It is not a moral failing or a lack of willpower. Signs people describe include needing more to get the same effect, difficulty cutting down, spending more time thinking about use, and continuing despite harm. Support is available at any stage — you do not need to have reached a crisis point. If you are worried, a prescriber or pharmacist can review your medicines with you.

Withdrawal

Do not stop prescribed medicines suddenly. Reductions should be planned with your prescriber, who can adjust the pace to suit you.

Overdose risks

Excessive doses of sedating medicines, especially in combination, can stop breathing. Paracetamol overdose can be serious even when someone feels well. Call 999 or 111 without delay.

Mixing substances

Alcohol and other sedating substances add to the effect of many medicines. Always ask a pharmacist before combining medicines.

Harm-reduction information

  • Ask your pharmacist for a medicines review
  • Keep a list of everything you take, including over-the-counter products
  • Return unused medicines to a pharmacy
  • Never share prescribed medicines

When to seek urgent medical help

Call 999 if someone is unconscious or cannot be woken, is having difficulty breathing, has a seizure, has chest pain, becomes very confused or agitated, or you are worried they may have overdosed. For urgent advice that is not life-threatening, call NHS 111. You will not get someone into trouble by calling for medical help.

Treatment and recovery options

  • Talking therapies and structured psychosocial support
  • Community drug and alcohol services, including self-referral where available
  • Medication-assisted treatment where clinically appropriate
  • Medically supported withdrawal, arranged and monitored by clinicians
  • Peer support and recovery communities
  • Residential rehabilitation for some people, usually via assessment
  • Support for related needs — mental health, housing, family and welfare

UK support resources

  • NHS — health information and service finders (nhs.uk)
  • Talk to FRANK — UK drug information service (talktofrank.com)
  • Your local community drug and alcohol service — many accept self-referrals
  • Local pharmacy teams, who can offer advice and signposting

Sources / references

This page is a plain-language summary written for education. For clinical or legal detail, use authoritative UK sources: NHS (nhs.uk), Talk to FRANK (talktofrank.com), NICE (nice.org.uk), UK Government and devolved government publications, and guidance from UK professional bodies. Each page on this site carries a review date, and we welcome corrections.

Is this an emergency?

If someone is unconscious, having difficulty breathing, may have overdosed, or is in immediate danger — call 999 now. You will not get anyone into trouble by calling for medical help.

For urgent but non-life-threatening concerns, NHS 111 can advise. A service finder never replaces emergency medical advice.

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