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Evaluation of contamination in preservative-free multi-dose Brimonidine eye drops: a comparative study
Serap Karaca1, Abdurrahman Sarmis2, Omer Faruk Yilmaz3
1Department of Ophthalmology, Goztepe Prof. Dr. Suleyman Yalcin City Hospital, Eğitim Mah. Fahrettin Kerim Gokay Caddesi Kadıkoy, Istanbul, 34722, Turkey. dr.serap44@gmail.com.
Purpose:
To investigate the effectiveness of preservative-free multi-dose eye drop technology in preventing contamination.
Study Design:
Prospective study METHODS: In this study, the caps, first and second drops of preservative-free multidose brimonidine (PF-MDB) and multidose brimonidine with purite preservative (P-MDB) used by 54 glaucoma patients were analysed on both chocolate and sheep blood agar. The patients used the drops at 3-week intervals. The contents of the eye droppers were examined for contamination by piercing the bottom of the eye dropper in accordance with aseptic techniques.
Results:
The contamination levels detected using chocolate agar in the caps and the first drops of PF-MDBs were significantly higher than in P-MDBs (p=0.006 and p<0.001, respectively). The contamination levels detected using blood sheep agar in the caps and the first and second drops of PF-MDBs were significantly higher than in P-MDBs (p=0.001, ‹0.001, 0.006, respectively). No growth was found inside the eye dropper bottles of either PF-MDB or P-MDB drops. There was a significantly higher level of contamination in the first drops of PF-MDB compared to the second drops (p<0.001).
Conclusion:
PF-MDB bottle technology effectively prevents microbial contamination in the bottle without preservatives. However, due to the lack of a preservative, there is increased bacterial and fungal growth associated with contamination on the cap, as well as in the first and second drops, compared to P-MDB.
Insights
Preservative-free multi-dose eye drops prevent bottle contamination but show higher microbial growth on caps and initial drops compared to preserved options. This highlights a trade-off between bottle sterility and external contamination risk.
Area of Science:
- Ophthalmology
- Microbiology
- Pharmaceutical Technology
Background:
- Multi-dose eye drops require effective strategies to prevent microbial contamination.
- Preservative-free formulations offer an alternative to traditional preserved eye drops, potentially reducing ocular surface toxicity.
- Assessing the microbial safety of preservative-free multi-dose eye drop technology is crucial for patient care.
Purpose of the Study:
- To evaluate the contamination prevention effectiveness of preservative-free multi-dose (PF-MDB) eye drop technology.
- To compare microbial contamination levels between PF-MDB and preserved multi-dose brimonidine (P-MDB) eye drops.
Main Methods:
- A prospective study involving 54 glaucoma patients using PF-MDB and P-MDB eye drops.
- Analysis of caps, first, and second drops from eye droppers on chocolate and sheep blood agar.
- Aseptic techniques were employed to examine for microbial contamination.
Main Results:
- No microbial growth was detected inside the bottles of either PF-MDB or P-MDB.
- Significantly higher contamination levels were observed on the caps and initial drops of PF-MDB compared to P-MDB.
- Contamination increased from the first to the second drop in PF-MDB, indicating a higher risk with subsequent uses.
Conclusions:
- Preservative-free multi-dose bottle technology successfully prevents internal microbial contamination.
- The absence of preservatives in PF-MDB leads to increased bacterial and fungal growth on external components like caps and initial drops.
- A balance must be considered between the benefits of preservative-free formulations and the increased risk of external microbial contamination.
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