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Blocking or enhancing effects of some basic emollients in UVA penetration
Sevgi Akarsu1, Emel Fetil1, Ozlem Ozbagcivan1
1Department of Dermatology, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey.
Anais Brasileiros De Dermatologia
|May 4, 2018
Summary
White petrolatum and basis cream applied before psoralen plus ultraviolet A (PUVA) therapy are not recommended due to their blocking effects. Glycerine and olive oil may be suitable for photochemotherapy, but further research is needed.
Area of Science:
- Dermatology
- Photobiology
- Pharmacology
Background:
- Topical agents can influence ultraviolet (UV) radiation transmission during phototherapy.
- Understanding these interactions is crucial for optimizing treatment efficacy and safety.
Purpose of the Study:
- To investigate the in vivo effects of common topical agents on ultraviolet A (UVA) radiation transmission.
- To determine the impact of petrolatum, basis cream, glycerine, and olive oil on the minimal phototoxic dose (MPD) in PUVA therapy.
Main Methods:
- A study involving 29 volunteers assessed the MPD with psoralen plus UVA (PUVA) alone.
- The MPD was re-evaluated after applying white petrolatum, basis cream, glycerine, olive oil, or sunscreen prior to PUVA exposure.
Main Results:
- White petrolatum significantly increased the MPD, indicating a blocking effect on UVA transmission.
- Basis cream, glycerine, and olive oil did not significantly alter the MPD compared to PUVA alone.
Conclusions:
- White petrolatum and basis cream should not be used immediately before PUVA therapy due to potential interference.
- Glycerine and possibly olive oil may be considered for use before photochemotherapy, pending further investigation in larger patient cohorts.
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