Opioid Overdose Recognition and Naloxone Use in Pharmacy
How to recognise an opioid overdose in or near the pharmacy, when and how to use naloxone, and the pharmacist's role in take-home naloxone supply and harm reduction.
Why this matters
Drug poisoning deaths in England and Wales have continued to rise. In 2024, opiates and opioids were involved in just under half of all registered drug-poisoning deaths, rising to around 60% when deaths with no drug type recorded are excluded.5 Community pharmacies are on the front line: they supply methadone and buprenorphine for supervised consumption, dispense prescribed opioids, and are often located in areas where people who use drugs may be present. A patient or bystander presenting at the counter with a collapsed or unresponsive individual nearby is a scenario that any pharmacist may face.
Respiratory depression is the mechanism by which opioid overdose kills. Opioids suppress the brain's drive to breathe, causing breathing to become progressively slower, shallower, and eventually absent. It is the rate and depth of breathing that determines the urgency of the response. Any unresponsive person with slow, shallow, gasping, or absent breathing requires immediate action.6
Risk is significantly increased when opioids are combined with other sedating substances. Alcohol, benzodiazepines, pregabalin, gabapentin, z-drugs, and other central nervous system depressants potentiate opioid-induced respiratory depression and are frequently implicated in fatal overdoses. Tolerance also plays a critical role: people recently released from prison, those who have completed detoxification, or those who have experienced any period of reduced opioid use have substantially lower tolerance and are at greatly increased risk at doses that previously caused them no harm.
Naloxone is a fast-acting opioid antagonist that can reverse opioid-induced respiratory depression within minutes. Naloxone is a prescription-only medicine, but anyone can administer available naloxone in an emergency to save a life. Since December 2024, pharmacists and pharmacy technicians are named professionals who may supply take-home naloxone without a prescription, PGD or PSD, provided they are suitably trained and acting within appropriate governance. This power is enabling, not mandatory.4
Red flags vs more likely benign
| Feature | More likely benign | Red flag ⚠ |
|---|---|---|
| Breathing | Normal rate and effort | Slow, shallow, irregular, gasping, or absent breathing: this is the most important sign of life-threatening opioid overdose |
| Consciousness | Alert and responsive to voice | Drowsy, difficult to rouse, unconscious, or unresponsive |
| Airway sounds | Quiet, normal breathing | Gurgling, snoring, or other signs of airway obstruction |
| Skin and lips | Normal colour and temperature | Pale, cold, clammy, or blue-tinged lips and fingertips: suggests cyanosis from inadequate breathing |
| Pupils | Normal size and reactive to light | Pinpoint pupils poorly reactive to light. Note: absence of pinpoint pupils does not exclude overdose, particularly with synthetic opioids or mixed presentations |
| Muscle tone | Normal | Limp or floppy |
| Response to stimuli | Responds to voice or gentle touch | No response to voice or gentle physical stimulation |
Breathing Is the Priority
In opioid overdose, it is the breathing that kills. The following points should guide every pharmacist's assessment.
- A drowsy or difficult-to-rouse person with suspected opioid exposure requires 999 assessment and close monitoring, even if breathing is currently adequate. Respiratory depression can worsen rapidly, especially when opioids are combined with alcohol, benzodiazepines, gabapentinoids, methadone, buprenorphine, fentanyl, or unknown substances.
- Slow, shallow, or absent breathing is the most important sign of life-threatening opioid overdose. A patient who is unresponsive with abnormal breathing requires CPR and immediate naloxone.6
- Absence of pinpoint pupils does not exclude opioid overdose. Synthetic opioids, mixed overdoses, and severe hypoxia can all alter the classic presentation. Act on the clinical picture, not the pupils alone.
- Naloxone wears off before many opioids. Recurrent respiratory depression can occur after apparent recovery, particularly with long-acting opioids such as methadone and buprenorphine. This is why ambulance assessment is required even if the person appears to recover after naloxone.
If in doubt about the cause of collapse, follow basic life-support procedures, call 999, retrieve and attach an AED if available, and administer naloxone if opioid overdose is suspected.
🛑 OVERDOSE: Pharmacy Response Framework
Use this sequence when opioid overdose is suspected.
Is breathing slow, shallow, gasping, irregular, or absent? This is the most critical assessment. Rate and depth of breathing determine urgency.
Call their name and try to rouse. No response to voice or touch requires immediate action.
Call 999 immediately for any unresponsive person. Put the phone on speaker. Assess breathing while waiting for the call to connect. Ask someone to retrieve the AED and attach it as soon as available.
If breathing normally: recovery position. If unresponsive with abnormal, slow, gasping, or absent breathing: assume cardiac arrest, start CPR, and follow AED and 999 call-handler instructions. Naloxone does not replace CPR.
Stay with the patient at all times. Do not allow a drowsy patient to leave the premises unaccompanied.
Maintain the airway throughout. Airway obstruction from loss of muscle tone is a common cause of deterioration.
Administer naloxone according to training, the product instructions, and local protocols. Multiple doses may be needed. Repeat dosing intervals vary by product: follow product instructions and 999 call-handler advice.
Naloxone wears off before the opioid. All patients need ambulance assessment even after apparent recovery. Patients may become agitated or experience withdrawal symptoms after naloxone administration.
What to do in pharmacy
Also call 999 if there are signs of cyanosis, airway obstruction, or suspected overdose with reduced consciousness. If the patient is breathing normally and the airway can be maintained, place them in the recovery position.
If naloxone is available, administer it according to training, the product instructions, and local protocols. Common UK naloxone products include Prenoxad intramuscular injection, Nyxoid nasal spray, and naloxone 1.26 mg nasal spray. Always follow the specific product instructions and local protocol. Repeat dosing intervals vary by product: follow product instructions and 999 call-handler advice. Continue CPR or airway support as needed between doses. The aim of naloxone is to restore adequate breathing and airway protection, not necessarily to make the person fully alert.7
Even if the patient appears to recover after naloxone, they must be assessed by emergency medical services. Naloxone wears off before many opioids, and recurrent respiratory depression can occur, particularly with long-acting opioids such as methadone and buprenorphine. Patients may also become agitated or experience withdrawal symptoms after naloxone administration.
Consider what opioid has been taken, when it was taken, and whether alcohol, benzodiazepines, pregabalin, gabapentin, or other sedating substances have also been used, as combinations significantly increase risk.
Patients taking prescribed opioids who become unexpectedly sedated, particularly following a dose increase or the addition of another sedating medicine, require urgent assessment. Patients receiving supervised methadone who appear unusually sedated require urgent clinical assessment before leaving. Ask whether naloxone has already been given by a bystander.
Pharmacy naloxone supply should follow local governance covering staff competence, product choice, storage, access in an emergency, expiry-date checks, replacement arrangements, record-keeping, and training. Supply records should allow the pharmacy to demonstrate appropriate supply and support stock control, monitoring, and replacement before expiry.
When supplying naloxone, provide clear verbal and written advice on recognising overdose, calling 999, administering naloxone, placing the person in the recovery position, staying with them until help arrives, and giving further doses if required. Current UK naloxone products include Prenoxad intramuscular injection, Nyxoid nasal spray, and naloxone 1.26 mg nasal spray.
Proactively consider naloxone for patients prescribed high-dose opioids, those prescribed opioids alongside benzodiazepines or gabapentinoids, those receiving opioid substitution therapy, those recently released from prison, those who have recently completed detoxification or experienced a period of abstinence, and those with a history of overdose. Consider safeguarding concerns where overdose involves a young person, coercion, homelessness, domestic abuse, exploitation, or an adult who may lack capacity.
Naloxone supply is one of the most effective harm-reduction interventions available in community pharmacy.
Key takeaways
- For any unresponsive person: call 999 immediately, assess breathing while waiting for the call to connect, start CPR if unresponsive with abnormal or absent breathing, attach an AED as soon as available, and administer naloxone if opioid overdose is suspected. Naloxone does not replace CPR.
- Slow, shallow, or absent breathing is the most important sign of life-threatening opioid overdose. A drowsy but rousable person still requires 999 assessment and close monitoring because respiratory depression can worsen rapidly, especially with polydrug use.
- Since December 2024, pharmacists and pharmacy technicians may supply take-home naloxone without a prescription, PGD or PSD if suitably trained. Proactively offer it to anyone at risk: high-dose opioids, opioids with benzodiazepines or gabapentinoids, opioid substitution therapy, recent abstinence, or history of overdose.
📚 References
- National Institute for Health and Care Excellence. Drug misuse prevention: targeted interventions. NG64. London: NICE; 2017. https://www.nice.org.uk/guidance/ng64
- NHS England. Commissioning guidance for naloxone. London: NHS England; 2022. https://www.england.nhs.uk/publication/commissioning-guidance-for-naloxone/
- Royal Pharmaceutical Society. Naloxone for opioid reversal: guidance for pharmacists. London: RPS; 2023. https://www.rpharms.com/recognition/all-our-campaigns/naloxone
- Department of Health and Social Care. Supplying take home naloxone without a prescription. GOV.UK; 2025 (updated September 2025). https://www.gov.uk/government/publications/supplying-take-home-naloxone-without-a-prescription
- Office for National Statistics. Deaths related to drug poisoning in England and Wales: 2024 registrations. ONS; 17 October 2025. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsrelatedtodrugpoisoninginenglandandwales/2024registrations
- Resuscitation Council UK. Adult basic life support guidelines. London: RCUK; 2025. https://www.resus.org.uk/library/2021-resuscitation-guidelines/adult-basic-life-support-guidelines
- Specialist Pharmacy Service. Reversing an adult opioid overdose with naloxone. SPS; updated March 2026. https://www.sps.nhs.uk/articles/reversing-an-adult-opioid-overdose-with-naloxone/
- Joint Formulary Committee. Naloxone hydrochloride. British National Formulary. London: BMJ Group and Pharmaceutical Press. https://bnf.nice.org.uk/drugs/naloxone-hydrochloride/