What is the COWS used for?

The COWS is used to measure the severity of opioid withdrawal in patients with opioid use disorder. A trained clinician scores 11 observed signs and reported symptoms to produce a total that reflects current withdrawal severity, guiding clinical decision-making about the timing of care and prompting follow-up as symptoms change.

How many items are on the COWS and how is it scored?

The COWS has 11 items covering autonomic signs, neuromuscular signs, patient-reported symptoms, and pupil size. Most items are scored from 0 to 4 and several from 0 to 5, producing a total between 0 and 48. Higher totals indicate more severe withdrawal at the moment of assessment.

What do COWS scores mean?

Published bands classify a total of 5 to 12 as mild withdrawal, 13 to 24 as moderate, 25 to 36 as moderately severe, and above 36 as severe. Scores below 5 suggest minimal or no withdrawal. Because severity shifts quickly, interpret any score alongside the full clinical picture.

Who administers the COWS?

A trained clinician or nurse administers the COWS, because scoring depends on accurate observation of signs such as pupil size, sweating, and gooseflesh alongside patient-reported symptoms. It is completed at the bedside in a few minutes and is often repeated across a shift to track how withdrawal is progressing.

Is the COWS copyrighted?

The COWS was published by Wesson and Ling in 2003 and is freely available for clinical use. It is reproduced in public resources from the National Institute on Drug Abuse and other agencies, so practices can use it without a license, though you should always cite the original source.

How often should the COWS be repeated?

There is no single fixed interval; the COWS is repeated as often as the clinical situation requires, often every few hours during active withdrawal or induction. Reassessing captures whether symptoms are intensifying or easing, which supports timely follow-up and helps teams monitor a patient's trajectory over time.

Clinical Opiate Withdrawal Scale | Template & auto-scoring

The Clinical Opiate Withdrawal Scale (COWS) is an 11-item, clinician-administered tool that measures the severity of opioid withdrawal through observed signs and patient-reported symptoms. A trained rater scores each item during a brief examination, and the total reflects how far withdrawal has progressed at that moment, guiding clinical decision-making for patients with opioid use disorder.

Why healthcare providers use the COWS

Objective severity measure. The COWS converts scattered withdrawal signs into a single number, so severity is documented consistently rather than described in vague terms.
Supports timing decisions. Clinicians use the score to judge how far withdrawal has progressed, which guides clinical decision-making about next steps.
Tracks change over time. Repeat scoring shows whether withdrawal is intensifying or easing, prompting follow-up when the trend shifts.
Shared clinical language. A COWS number communicates severity clearly across nurses, physicians, and care teams during handoffs.
Fast to complete. A trained rater can finish the assessment in a few minutes at the bedside.

Which settings use the COWS?

Emergency and urgent care. Teams assess suspected opioid withdrawal in patients who present acutely.
Addiction medicine and MAT clinics. Programs use the score during buprenorphine induction and ongoing care.
Inpatient and detox units. Nursing staff score withdrawal repeatedly across a shift to monitor progression.
Primary care. Clinicians managing opioid use disorder gauge withdrawal during office visits.

What does the COWS measure?

The COWS combines objectively observed signs with symptoms the patient reports, captured at a single point in time. It reflects the current state of withdrawal rather than a diagnosis, and it covers four broad domains.

Autonomic signs. Resting pulse rate, sweating, gooseflesh skin, and runny nose or tearing.
Neuromuscular signs. Tremor, restlessness, yawning, and bone or joint aches.
Patient-reported symptoms. Gastrointestinal upset and anxiety or irritability.
Examination findings. Pupil size assessed by the rater.

Scoring the COWS

Number of items. 11 items covering observed signs and reported symptoms.
Per-item scale. Each item uses an ordinal rating, with most items scored 0 to 4 and several scored 0 to 5.
Total score range. 0 to 48.
Score direction. Higher totals indicate more severe withdrawal.

The COWS reflects severity at the moment of assessment and can change quickly, so a single score is best interpreted alongside the clinical picture and repeated as needed. Totals below 5 generally indicate minimal or no withdrawal. The score supports, and does not replace, clinical judgment.

Score	Interpretation	Suggested next step
5-12	Mild withdrawal	Monitor and reassess
13-24	Moderate withdrawal	Consider further assessment
25-36	Moderately severe withdrawal	Consider further assessment
>36	Severe withdrawal	Immediate evaluation

Best practices for administration

Use a trained rater. Scoring relies on accurate observation of signs like pupil size and gooseflesh, so the person administering it should know the criteria.
Score at rest. Measure resting pulse and observe the patient calmly, since recent activity can distort several items.
Note timing and context. Record when the last opioid use occurred, because withdrawal severity shifts with time.
Repeat to track progression. Reassess at intervals to capture whether withdrawal is building or resolving.
Interpret alongside the whole picture. Combine the score with vital signs, history, and clinical judgment.

How Zentake helps with the COWS

Automatic scoring. Totals are calculated on submit, so there is no hand-tallying.
Longitudinal tracking. Re-send the COWS on a schedule and view change over time.
Risk flagging. Concerning responses are surfaced to staff so high severity is not missed.
Before the visit. In urgent care practices, staff can capture symptom history on any device so the clinician starts the assessment informed.
HIPAA compliant. Data is encrypted, with a signed BAA on every plan.

References

The COWS was developed and validated by Wesson and Ling (2003), The Clinical Opiate Withdrawal Scale (COWS), Journal of Psychoactive Drugs, 35(2), 253 to 259.

The severity bands shown above appear on the Clinical Opiate Withdrawal Scale form distributed by the National Institute on Drug Abuse.

Last updated: August 2026

Clinical Opiate Withdrawal Scale