Substance
What not to mix with Codeine (lean)
Opioid
Also calledlean, purple drank, co-codamol, dihydrocodeine
Weak, but metabolised unpredictably between people
Summary
Codeine is checked against 40 other substances — 12 dangerous, 3 unsafe and 9 caution.
Dangerous
12- Codeine and AlcoholHow strong codeine is varies hugely from person to person, and alcohol adds its own slowed breathing on top. Do not combine. Keep naloxone nearby.
- Codeine and BenzodiazepinesTogether they slow breathing, and codeine's strength is unpredictable. Do not combine. Keep naloxone nearby.
- Codeine and CocaineCocaine hides how much the opioid is slowing you down, so you take more; when the cocaine wears off first, breathing can stop. Do not combine. Keep…
- Codeine and DXMTogether they slow breathing and strain the heart and liver, and DXM makes the opioid hit harder. Do not combine. Keep naloxone nearby.
- Codeine and FentanylFentanyl sets the risk; codeine adds little effect and real danger. Do not combine. Keep naloxone nearby.
- Codeine and GHB / GBLEach makes the other much stronger, fast and unpredictably, so people pass out quickly. Do not combine. Keep naloxone nearby, and put anyone who…
- Codeine and KetamineTogether they can cause vomiting and unconsciousness. Do not combine. Keep naloxone nearby, and put anyone who passes out on their side.
- Codeine and MethadoneCodeine adds slowed breathing on top of methadone's build-up, for very little extra effect. Do not combine. Keep naloxone nearby.
- Codeine and MXEMXE can make the opioid hit harder. Do not combine. Keep naloxone nearby.
- Codeine and OpioidsCodeine adds a lot of slowed breathing for very little extra effect. Do not combine. Keep naloxone nearby.
- Codeine and PregabalinHigh risk of death or life-changing injury. Do not combine.
- Codeine and TramadolTramadol raises the seizure risk, and together they can slow breathing. Do not combine. Keep naloxone nearby.
Unsafe
3- Codeine and DiphenhydramineEach makes the other stronger, raising the risk of memory loss, collapse and unconsciousness. Avoid this combination. Keep naloxone nearby.
- Codeine and KratomKratom varies between batches and codeine varies between people, so neither dose means what you think. Avoid this combination.
- Codeine and MethamphetamineMeth hides how much the opioid is slowing you, and when it fades, everything you redosed hits at once, often as you fall asleep. Avoid this…
Caution
9- Codeine and AcetaminophenMost codeine tablets already contain acetaminophen, so more codeine means more acetaminophen, and liver damage gives no warning for a day or more…
- Codeine and AmphetaminesThe stimulant hides how much the opioid is slowing you; if it wears off first, breathing can stop. Take less of each than usual, do not use alone…
- Codeine and BuprenorphineBuprenorphine largely blocks codeine, so the codeine does little. Do not keep escalating it.
- Codeine and LithiumTogether they add sedation, and dehydration can push lithium levels up. Keep up water, and keep naloxone nearby.
- Codeine and MAOIsWith certain opioids, MAOIs have caused rare but severe and fatal reactions. Take less of each than usual, do not use alone, and keep naloxone nearby.
- Codeine and MephedroneThe stimulant hides how much the opioid is slowing you; if it wears off first, breathing can stop. Take less of each than usual, do not use alone…
- Codeine and Nitrous OxideEach makes the other stronger, so you can lose balance or pass out without warning. Take less of each than usual, do not use alone, and keep naloxone…
- Codeine and PCPPCP can lower your opioid tolerance, making an overdose more likely. Take less opioid than usual, do not use alone, and keep naloxone nearby.
- Codeine and SSRIsSome SSRIs stop codeine working, which tempts redosing, and if the SSRI changes, the same dose can hit far harder. Do not redose to chase the effect.
Low / synergy
1Low / no synergy
15Checking more than one?
This page rates Codeine against one substance at a time. Combinations of three or more carry risks that no pair-by-pair list can show — the checker rates every pair at once and flags the whole-mix ones on top.
Open Codeine in the checkerOther opioids
All combinations →Educational information only, not medical advice. Absence of a documented interaction is not evidence of safety. Combination data from the TripSit drug combination chart, retrieved 2026-08-20.