PlainPill

Codeine

Based on 4 first-hand reports and 134 meta-analyses & systematic reviews in the medical literature. Ranked #2104 of 4,149 overall.

14
User score
Mostly negative
25% positive0% mixed25% negative50% unclear

Of reports that state an outcome, 50% are positive.

Clinical research
AStrong research base
134
meta-analyses
496
RCTs
6,296
papers

What Codeine does, according to users

Of the people who reported each effect, the share who said it got better.

No specific effects reported yet.
betterno changeworse

What the research says

Systematic reviews and meta-analyses from PubMed, with their published conclusions.

AStrong research base

3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.

Vet Anaesth Analg · 2021 · Meta-analysis / systematic review
Efficacy of tramadol for postoperative pain management in dogs: systematic review and meta-analysis

Conclusion: Overall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26-0.85; I2 = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20-1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16-3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00-0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95%

PubMed 33745825 ↗
Cochrane Database Syst Rev · 2023 · Meta-analysis / systematic review
Cannabis-based medicines and medical cannabis for adults with cancer pain

Conclusion: There is moderate-certainty evidence that oromucosal nabiximols and THC are ineffective in relieving moderate-to-severe opioid-refractory cancer pain. There is low-certainty evidence that nabilone is ineffective in reducing pain associated with (radio-) chemotherapy in people with head and neck cancer and non-small cell lung cancer. There is low-certainty evidence that a single dose of synthetic THC analogues is not superior to a single low-dose morphine equivalent in reducing moderate-to-severe cancer pain. There is low-certainty evidence that CBD does not add value to specialist palliative c

PubMed 37283486 ↗
J Dent Res · 2023 · Meta-analysis / systematic review
Acute Postoperative Pain Due to Dental Extraction in the Adult Population: A Systematic Review and Network Meta-analysis

Conclusion: Based on low- and very low-certainty evidence, most interventions were classified as no more harmful than placebo for most adverse effects. Based on moderate- and high-certainty evidence, NSAIDs with or without acetaminophen result in better pain-related outcomes than opioids with or without acetaminophen (except acetaminophen 650 mg plus oxycodone 10 mg) or placebo.

PubMed 36631957 ↗
Cochrane Database Syst Rev · 2017 · Meta-analysis / systematic review
Opioids for cancer pain - an overview of Cochrane reviews

Conclusion: The amount and quality of evidence around the use of opioids for treating cancer pain is disappointingly low, although the evidence we have indicates that around 19 out of 20 people with moderate or severe pain who are given opioids and can tolerate them should have that pain reduced to mild or no pain within 14 days. This accords with the clinical experience in treating many people with cancer pain, but overstates to some extent the effectiveness found for the WHO pain ladder. Most people will experience adverse events, and help may be needed to manage the more common undesirable adverse effe

PubMed 28683172 ↗

Dosage people report

As stated by users — not a recommendation. Follow the label or your doctor.

2 mlas reported
150mgas reported
5 mgas reported

Reported side effects

How often each side effect came up across all reports.

restlessness ×1discomfort ×1

What users say

First-hand experiences, quoted verbatim. We show one positive and one negative where both exist.

“I've had developed a permanent tolerance to codeine's euphoriant effects, but during my 20 day BPC-157 500mcg/day cycle I've tried codeine once...It felt like the first times.”
HelpedRead the discussion ↗
“This is now my second time trying codeine and I don't like it. Maybe I'm not having enough to feel the drowsy side of it, but both times, it's made me feel uncomfortable and restless. 4/10, would not try again.”
Didn't helpRead the discussion ↗
Top discussions (4)

More medications

User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 3, 2026. How we rate