Medications
Opioid Painkillers Before Surgery
If you take opioid painkillers regularly, the big question before an operation is whether to keep taking them. In most cases the answer is yes, but your anaesthetic team needs to know.
Quick answer
The one thing you must do is tell your anaesthetic team well before the day. Because your body is used to opioids, your pain after surgery can be harder to control and you may need different or higher-dose pain relief than someone who doesn't take them. Buprenorphine (including the Butrans patch, Buvidal long-acting injection, or Subutex/Suboxone) and methadone are special cases that need a specific plan made in advance — see below. Do not change these yourself.
Why it matters
Opioids change how your body and brain handle pain. When you take them regularly, you build up tolerance, meaning a given dose does less than it used to. Your nervous system adapts to having the drug on board, so if it suddenly disappears around the time of surgery you can go into withdrawal — sweating, cramps, racing heart, agitation and a spike in pain — exactly when you need to be calm and comfortable. That is why the usual plan is to continue your normal opioid through the operation rather than stop it.
Tolerance also means your 'baseline' need for pain relief is higher than average. Surgery adds fresh pain on top of that. If the team doesn't know you take opioids, the standard after-surgery doses may simply not be enough, and you can end up under-treated and distressed. When they do know, they can plan ahead — combining your regular opioid with other types of pain relief (such as paracetamol, anti-inflammatories, nerve blocks or regional anaesthesia) so you are covered properly and safely.
A few opioids behave differently and need careful handling. Buprenorphine and methadone interact with other opioids in ways that affect how well post-surgery pain relief works, and decisions about whether to continue, adjust or bridge them must be made by your team in advance — not by you, and not on the morning of surgery. Sharing your exact medicines, doses, and any patch change days or injection dates lets them build the right plan.
Do not stop without instruction
Equally, this is not something to manage solo. The right move is coordination, not a unilateral change: tell your surgical and anaesthetic team exactly what you take — drug names, doses, how often, any patches or long-acting injections, and the date you last changed a patch or had an injection — and let them direct any adjustments. This matters most for buprenorphine and methadone, which require a specific, planned approach decided with the team before the day. If you also take other regular medicines, see our guide to medications to stop before surgery and run your full list through the medication checker — but bring opioids up directly with a person, not just a checklist.
What to ask your doctor
- I take [name your opioid, dose and how often, plus any patches or injections] — should I continue right up to and on the morning of surgery?
- I use a buprenorphine or methadone product — what is your specific plan for it around my operation, and when should that start?
- Because I'm opioid-tolerant, how will you make sure my pain is controlled after surgery, and what extra options will you use?
- What is the plan for my opioids during recovery and when I go home, including how to come back to my normal dose safely?
Red flags — call your team
Red flags — call your team
- Withdrawal symptoms if doses are missed or delayed — sweating, shivering, muscle cramps, stomach upset, agitation or a racing heart — tell staff straight away.
- Severe, uncontrolled pain after surgery that your current pain relief isn't touching; you may need your regimen reviewed rather than simply waiting it out.
- Excessive drowsiness, confusion, very slow or shallow breathing, or hard-to-wake sleepiness — signs of too much opioid effect that need urgent medical attention.
References
- Guidance from anaesthetic and pain bodies (for example the Association of Anaesthetists, the Royal College of Anaesthetists and Faculty of Pain Medicine, and ASRA-type perioperative recommendations) advises continuing regular opioids through surgery to avoid withdrawal, and making a specific advance plan for buprenorphine and methadone.
- These pages are general information, not personal medical advice. Your own surgical and anaesthetic team know your history and medicines — their instructions always take precedence over anything written here.
Frequently asked questions
Should I take my opioid on the morning of surgery?
Usually yes. For regular or long-term opioids, most teams want you to take your normal dose on the morning of the operation with a small sip of water, so you don't go into withdrawal or start the day in extra pain. Always confirm this with your anaesthetic team beforehand, because buprenorphine, methadone and some patches may have specific instructions that differ from your tablets.
Will my usual painkillers still work after surgery?
Because you're opioid-tolerant, standard after-surgery doses may not be enough, so your pain can be harder to control. That's exactly why you should tell the team in advance. They can plan higher or different opioid doses alongside other methods — paracetamol, anti-inflammatories, nerve blocks or regional anaesthesia — to keep you comfortable safely. Being under-treated is a real risk if they don't know you take opioids.
Do I need to do anything special about my fentanyl or buprenorphine patch?
Yes — mention patches specifically and tell the team the date you last changed one. Fentanyl patches are usually continued, but buprenorphine products (such as the Butrans patch, or the Buvidal long-acting injection) affect how other opioids work and need an advance plan. Don't remove, change or skip a patch, or alter a buprenorphine product, on your own. Let your anaesthetic team decide what happens with it before the day of surgery.
Can't I just stop my opioids before surgery to be safe?
No. Stopping regular opioids abruptly can cause withdrawal — sweating, cramps, agitation, a racing heart — and rebound pain, which makes surgery and recovery harder. Your tolerance also doesn't disappear quickly, so you'd face fresh surgical pain with less protection. The safe approach is to continue as normal and let your team coordinate any changes, rather than cutting down or stopping by yourself.