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Abstract. Most medications are not absorbed topically due to the stratum corneum barrier. While effective a s a topical anesthetic, EMLA cream is absorbed slowly, delaying its effects for up to one hour, thereby limiting its usefulness. Objective: To determine whether removal of the cornified layer of the skin by tape stripping (TS) would allow more rapid onset of anesthesia after topical application of EMLA cream prior to IV catheterization (IVC). Methods: This was a prospective, randomized, controlled trial comparing the levels of pain of IVC 15 minutes after topical application of EMLA cream in patients who had TS vs patients who did not. The setting was a suburban university-affiliated ED. A convenience sample of 68 alert adult patients requiring IVC were enrolled. The primary outcomes measured were pain of IVC and pain of TS using a previously validated 100-mm visual analog scale as well as the IVC success rate. Results: The pain of IVC was less for TS vs control patients [29.7 mm (95% CI = 20.4 to 39.0 mm) vs 15.9 mm (95% CI = 9.1 to 22.6 mm), p = 0.0171. The mean pain of TS was 4.8 2 7.4 mm. The IVC success rate for TS vs control patients was 91% vs 74% (p = 0.056). There were no adverse events after TS. Conclusions: Removal of the cornified layer of the skin resulted in a more rapid anesthetic effect of EMLA cream as evidenced by lower IVC pain scores after TS. The effectiveness of TS for enhanced absorption of other medications should be investigated. Key words: tape stripping; permeability; absorption; drug delivery; stratum corneum; cutaneous tape stripping. ACADEMIC EMERGENCY MEDI-CINE 1998; 5:1051-1056 SE OF the skin for topical delivery h a s U many potential advantages over local injection of drugs such a s local anesthetics and immunizations. In addition to eliminating the pain and fear associated with local topical delivery avoids the risk of introducing infection, eliminates the occupational risk of unintentional needlesticks, bypasses the gastrointestinal tract and liver, and may serve a s a drug reservoir for sustained release.Unfortunately, topical delivery has been limited by the relative impermeability of the skin to most medications. The major barrier to topical absorp-

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