Comparison of Physical Properties and Annual Costs of Two Multi-dose Eye Drops Containing Latanoprost

Abstract

ABSTRACT Objectives: To compare of drop volume, number of drops per milliliter, number of drops in bottle, bottle volume and annual costs of two multi-dose eye drops containing latanoprost. Materials and Methods: Xalatan and Latapol eye drops available in Turkey were included in this study. The first 10 drops volume was measured with a micropipette and the average of the drop volume was found. The repeatability coefficient of the first 10 drops volume was calculated. Number of drops per milliliter, number of drops in bottle and bottle volume were measured in a graduated cylinder calibrated in increments of 0.1 ml. The annual cost was calculated based on the number of drops in the bottle. Results: The drop volume was 27.56 µl and 27.66 µl for Xalatan and Latapol, respectively (p=0.729). The lowest-highest drop volume and repeatability coefficient for Xalatan were 26-29 µl and ±1.39 µl, respectively, 25-30 µl and ±1.93 µl for Latapol. The number of drops per milliliter, the number of drops in the bottle and the bottle volume for Xalatan were 36.27 drops, 99 drops and 2.77 ml, respectively, 35.47 drops, 93.66 drops and 2.66 ml for Latapol (p=0.672, p=0.007 and p =0.008, respectively). The cost per drop and the annual cost for Xalatan were 0.2101 ₺ and 153.37 ₺ respectively, 0.2220 and 162.11 ₺ for Latapol (p=0.031 and p=0.010, respectively). Conclusion: The number of drops in bottle and bottle volume of Xalatan is significantly higher than Latapol, which causes the annual cost of Xalatan to be significantly lower. Key Words: Drop volume, Drop number, Eye drop, Latanoprost, Cost

Keywords

• Drop volume
• Drop number
• Eye drop
• Latanoprost
• Cost

Latanoprost İçeren İki Çoklu Doz Göz Damlasının Fiziksel Özelliklerinin ve Yıllık Maliyetlerinin Karşılaştırılması

Öz

ÖZ Amaç: Latanoprost içeren iki çoklu doz göz damlasının damla hacmi, mililitredeki damla sayısı, şişedeki damla sayısı, şişe hacmi ve yıllık maliyetleri bakımından karşılaştırılması. Gereç ve Yöntem: Türkiye’de elde edilebilir olan Xalatan ve Latapol göz damlaları çalışmaya alındı. İlk 10 damlanın hacimleri mikropipetle ölçülüp ortalaması alınarak damla hacmi bulundu. İlk 10 damla için tekrarlanabilirlik katsayısı hesaplandı. Mililitredeki damla sayısı, şişedeki damla sayısı ve şişe hacmi hesaplanırken 0.1 ml’lik artışları olan dereceli silindir kullanıldı. Yıllık maliyet şişedeki damla sayısına göre hesaplandı. Bulgular: Damla hacmi Xalatan ve Latapol için sırasıyla 27.56 µl ve 27.66 µl idi (p=0.729). Xalatan için en düşük-en yüksek damla hacmi ve tekrarlanabilirlik katsayısı sırasıyla 26-29 µl ve ±1.39 µl, Latapol için ise 25-30 µl ve ±1.93 µl bulundu. Xalatan için mililitredeki damla sayısı, şişedeki damla sayısı ve şişe hacmi sırasıyla 36.27 damla, 99 damla ve 2.77 ml, Latapol için ise 35.47 damla, 93.66 damla ve 2.66 ml idi (sırasıyla p=0.672, p=0.007 ve p=0.008). Xalatan için damla başına maliyet ve yıllık damla maliyeti sırasıyla 0.2101 ₺ ve 153.37 ₺, Latapol için ise 0.2220 ₺ ve 162.11 ₺ idi (sırasıyla p=0.031 ve p=0.010). Sonuç: Xalatan’ın şişedeki damla sayısı ve şişe hacmi Latapol’dan anlamlı olarak yüksek olup bu durum Xalatan’ın yıllık maliyetinin anlamlı olarak düşük olmasına yol açmaktadır. Anahtar Sözcükler: Damla hacmi, Damla sayısı, Göz damlası, Latanoprost, Maliyet

Anahtar Kelimeler

• Damla hacmi
• Damla sayısı
• Göz damlası
• Latanoprost
• Maliyet

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