COWS

Clinical Opiate Withdrawal Scale — 11 clinician-rated items, 0–48

Resting pulse rate (beats/min)

≤ 80

81–100

101–120

> 120

Sweating (past 30 min, not from activity or room temperature)

No chills or flushing

Subjective chills or flushing

Flushed or observable moistness on the face

Beads of sweat on the brow or face

Sweat streaming off the face

Restlessness during assessment

Able to sit still

Reports difficulty sitting still, but is able to

Frequent shifting or extraneous limb movements

Unable to sit still for more than a few seconds

Pupil size

Pinned or normal for the light

Possibly larger than normal

Moderately dilated

So dilated that only the rim of the iris is visible

Bone or joint aches (attributable to withdrawal)

Not present

Mild diffuse discomfort

Severe diffuse aching of joints or muscles

Rubbing joints or muscles, unable to sit still from discomfort

Runny nose or tearing (not from a cold or allergy)

Not present

Nasal stuffiness or unusually moist eyes

Nose running or tearing

Constant nasal discharge or tears streaming down the face

GI upset (past 30 min)

No GI symptoms

Stomach cramps

Nausea or loose stool

Vomiting or diarrhoea

Multiple episodes of diarrhoea or vomiting

Tremor (arms outstretched)

No tremor

Tremor can be felt but not observed

Slight tremor observable

Gross tremor or muscle twitching

Yawning during assessment

No yawning

Yawning once or twice during assessment

Yawning three or more times during assessment

Yawning several times a minute

Anxiety or irritability

None

Reports increasing irritability or anxiousness

Obviously irritable or anxious

So irritable or anxious that participation in the assessment is difficult

Gooseflesh skin

Smooth skin

Piloerection can be felt or hairs standing up

Prominent piloerection

Evidence

Original publication

Wesson DR, Ling W. The Clinical Opiate Withdrawal Scale (COWS). An 11-item clinician-rated scale (pulse, sweating, restlessness, pupil size, aches, rhinorrhoea/lacrimation, GI upset, tremor, yawning, anxiety, gooseflesh) scoring opioid withdrawal severity from 0 to 48.

Journal of Psychoactive Drugs, 2003

Open source

Guideline

Used to time and dose opioid-agonist treatment: buprenorphine induction is generally started at moderate withdrawal (COWS ≥ 8–12) to avoid precipitated withdrawal. Bands here: < 5 none, 5–12 mild, 13–24 moderate, 25–36 moderately severe, ≥ 37 severe.

Last reviewed: 2026-09

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MedScore is an educational and clinical decision-support tool. It does not provide a diagnosis, a treatment, or a drug-dosing recommendation, and it does not replace clinical judgement or local guidelines. Confirm every result against the original source before acting on it. The treating clinician remains responsible for all decisions.