CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-08-14). The draft was written by AI, the existence of all 2 cited sources was verified (1 access-limited, verified via index/summary and marked), and the verdict passed blind grading and adversarial audit. Methodology v0.7.
Verdict No. 2578 · Search date 2026-08-14 · Methodology v0.7

Z-track intramuscular injection,
does it really help with Reduced medication leakage onto the skin after injection?

30-Second Summary
C
Evidence Grade C · 50 · Safety caution
Z-track reduced skin-surface medication leakage but did not establish less tissue injury or failed absorption.
Risks arise mainly from intramuscular injection and diclofenac rather than the Z-track maneuver itself. Check bleeding risk, anticoagulants, local infection or nerve injury, and gastrointestinal, renal, and cardiovascular NSAID risks.
What the
research shows
The grade is C. In a randomized 60-person comparison, skin-surface leakage after 3 mL diclofenac was 6.93±4.62 mm with Z-track and 10.03±3.69 mm with standard injection (P=.008). The 3.10-mm difference divided by the pooled standard deviation is about 0.74, a medium-to-large magnitude. However, this measured leakage on paper, not tissue injury, failed absorption, or treatment benefit. Allocation concealment, blinding of the leakage assessor, and prospective registration were not confirmed in this single small trial, giving C with 50 points.
What the
ads claim
Z-track truly reduced the length of medication found on paper in this trial. That does not prove complete absorption or reduced tissue injury, pain, or treatment failure.
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Useful facts when choosing a product

  • Z-track displaces skin and subcutaneous tissue laterally before injection and releases it after needle withdrawal, offsetting the needle path.
  • Both groups received prescribed 3-mL diclofenac.
  • Leakage was measured immediately after injection on a 7-by-7-cm sterile paper with a millimeter ruler.
Gap Measurement · Verdict 2578 · C 50
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Yilmaz D, Khorshid L, Dedeoğlu Y et al. randomized 60 adult patients at a Turkish government hospital, 30 per group, to gluteal injection of prescribed 3-mL diclofenac by Z-track or standard technique. Immediately afterward, a 7-by-7-cm sterile paper was applied and leakage length measured with a millimeter ruler. A different nurse masked to technique assessed pain, but masking of the leakage assessor was not reported in publicly available material. No trial registration exists, and the original funding or acknowledgment section could not be verified.

02

Why this is classified as C (50)

Leakage decreased significantly with an approximate standardized magnitude of 0.74, but the outcome was a process surrogate from one small trial with unconfirmed concealment, leakage-assessor masking, and preregistration. This gives C with 50 points.

Counterpoint. Actual tissue injury, absorption failure, infection, and treatment effectiveness were not measured.

Rejudgment record. Cross-check applied — The original abstract and later systematic review were cross-checked for the 60-person analysis, leakage and pain means and standard deviations, measurement method, masked pain assessor, and unconfirmed concealment, registration, and funding.

Scoring profile behind this grade
EndpointSSurrogate marker - laboratory or imaging measures
ReplicationR1Single confirmatory trial
IndependenceI1Mixed funding sources
Effect sizeE+Meets the clinically important threshold

The scoring table and the verdict agree (C).

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Reduced skin-surface medication leakageCLeakage decreased from 10.03 to 6.93 mm.
Reduced injection painDThe pain difference was not significant.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Study 1Single-center semiexperimental randomized comparison30Original funding and acknowledgment section could not be verifiedSkin-surface medication leakage length immediately after injection and VAS painLeakage 6.93±4.62 versus 10.03±3.69 mm, P=.008, calculated d≈0.74; pain 28.30±23.0 versus 36.40±28.40, not significantSingle small process-surrogate trial
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Receipt — 2 References

Of 2 cited sources, 1 had limited original-page access (blocked or summary-only) and were verified via index/summary, marked partial; the rest were verified at the original page. As of 2026-08-14.

Yilmaz D, Khorshid L, Dedeoğlu Y, et al. The Effect of the Z-Track Technique on Pain and Drug Leakage in Intramuscular Injections. Clin Nurse Spec. 2016;30(6):E7-E12. PMID: 27753676. DOI: 10.1097/NUR.0000000000000245.
partial
Soliman E, Ranjan S, Xu T, et al. The effect of intramuscular injection technique on injection associated pain; a systematic review and meta-analysis. PLoS One. 2021;16(5):e0250883. PMID: 33939726. DOI: 10.1371/journal.pone.0250883.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-08-14 · Corrections: none

Cite this verdict

Z-track intramuscular injection x medication leakage Evidence Grade C card
[Chamgap] Z-track intramuscular injection x medication leakage — Evidence Grade C·50. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/skin-hair/z-track-intramuscular-injection-drug-leakage/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.