OBJECTIVE To examine the influence of vehicles on the stability of extemporaneous suspensions of proton pump inhibitors (PPIs), to single out the formulation most suitable for children, providing appropriate evidence and arguments. METHODS A review was performed of data identified from Medline, Embase, Science Direct, as well as public digital archive PubMed, including reference texts, related to the field of stability testing of extemporaneous PPI suspensions. RESULTS Fourteen selected formulations of extemporaneous suspensions are presented and discussed. Depending on the vehicle and its composition, which was analyzed and explained in detail, the suspensions had various beyond-use dates (BUDs). CONCLUSIONS Selected vehicles and the process of preparation had great influence on the stability of extemporaneous PPI suspensions. The suspension with the longest BUD has been singled out, which is especially suitable for use in newborns. Because an explanation is provided for the influence of individual vehicle components on the stability of the mentioned suspensions, this can aid not only in the selection of an adequate formulation, but also in the development of new ones, which will be suited to individual patients.

Development of solid self-nanoemulsifying drug delivery systems (s-SNEDDS) for oral delivery of lysozyme Merima Sirbubalo, Tamás Sovány, Katalin Kristó, Géza Regdon jr, Edina Vranić 1 University of Sarajevo, Faculty of Pharmacy, Department of Pharmaceutical Technology, Sarajevo, Bosnia and Herzegovina 2 University of Szeged, Faculty of Pharmacy, Institute of Pharmaceutical Technology and Regulatory Affairs, Szeged, Hungary

Dimenhydrinate (DMH) is used for the prevention and treatment of nausea, vomiting, dizziness and vertigo associated with motion sickness in a dose of 50 mg 1. It’s made of two drugs in a form of salt, diphenhydramine and 8-chlorotheophylline which synergically decrease motion caused neural excitation 2. DMH is classified as a slightly soluble drug and it belongs to class II of BCS classification as a drug with low solubility and high permeability 3. Cyclodextrins (CDs) are cyclic oligosaccharides formed by α-1,4-linked glucose units with a hydrophilic outer surface and a lipophilic central cavity. Formation of inclusion complex by incorporating a drug in the central CD cavity provides improvement of physicochemical properties without molecular modifications. Solubility and dissolution rate of poorly water-soluble drugs can be increased 4. Aqueous solubility of natural CDs is limited due to their tendency to form H-bonded associations. However, due to multiple reactive hydroxyl groups, their functionality can be greatly increased by chemical modification 5. CDs’ substituted derivates can overcome poor solubility issues and enhance bioavailability. Hydroxypropylβ-CD (HP-β-CD) has good inclusion ability, high water solubility and it’s safe for intravenous and oral administration 6. Stability constant (Ks) and complexation efficacy (CE) are important for assessing the binding characteristics of the drug and CD. They can be determined by the phase solubility studies where the change of the drug solubility is corresponding to the concentration of CD 7. Linear (AL) type of the curve implies that one molecule of the drug forms inclusion complex with one molecule of the CD. Apparent stability constant K1:1 can be calculated from the following equation:

Microneedles (MNs) represent the concept of attractive, minimally invasive puncture devices of micron-sized dimensions that penetrate the skin painlessly and thus facilitate the transdermal administration of a wide range of active substances. MNs have been manufactured by a variety of production technologies, from a range of materials, but most of these manufacturing methods are time-consuming and expensive for screening new designs and making any modifications. Additive manufacturing (AM) has become one of the most revolutionary tools in the pharmaceutical field, with its unique ability to manufacture personalized dosage forms and patient-specific medical devices such as MNs. This review aims to summarize various 3D printing technologies that can produce MNs from digital models in a single step, including a survey on their benefits and drawbacks. In addition, this paper highlights current research in the field of 3D printed MN-assisted transdermal drug delivery systems and analyzes parameters affecting the mechanical properties of 3D printed MNs. The current regulatory framework associated with 3D printed MNs as well as different methods for the analysis and evaluation of 3D printed MN properties are outlined.

© Author(s) (or their employer(s)) 2021. No commercial reuse. See rights and permissions. Published by BMJ. We come from Bosnia and Herzegovina, a small country in western Balkans. Our Faculty of Pharmacy at the University of Sarajevo was opened in 1973, but from then on there was no kind of online teaching. So when the COVID-19 pandemic broke out, and when the university decided to stop all kinds of ‘inclass’ teaching (12 March 2020), we were faced with something new. We work at the Department of Pharmaceutical Technology, where we teach regular courses on ‘Drug Formulation’ and ‘Industrial Pharmacy’. Students take classes in these subjects in the seventh, eighth and ninth semesters. The exercises are practical and last several hours. On 25 March 2020, classes in the lecture hall were suspended until further notice by the decision of the Senate of the University of Sarajevo, and then we realised that we must embark on the adventure of organising online classes. We carried out short research on available online teaching platforms to find basic information on the platform’s capabilities, identify their advantages and disadvantages, and check their commercial prices. We studied the following platforms for online courses: Google Meet, Adobe Connect, Zoom and BigBlueButton, and the following platforms for online examinations: Exam. net, Virtualx, Google Forms, Skillsbook, Papershala, Edbase, Kaldin and TCExam. After examining the possibilities of the available online teaching platforms, we agreed that Zoom and Google Meet provide the best results for running online courses. Adobe Connect, Blackboard Collaborate and BigBlueButton work on the same principle, but professional versions of these platforms were quite unaffordable to us. The results for the online examination platforms are summarised in table 1. Given the security and price of the platforms, we concluded that Exam. net currently meets our criteria, but that it would be necessary to use two platforms simultaneously during the examination, one of which would allow an established video connection with students during the examination (eg, a combination of Exam. net and Zoom). Students accessed the examination platform from their laptop while simultaneously established a video connection with the teacher on their mobile device. At the end of the semester, we conducted an online survey in which 60 (70.93%) of 86 students participated, and for 98.4% of the students this was their first online learning experience. Although it is assumed that current students (digital natives) have adequate information and communications technology competence, they differ in their computer and information literacy as they come from different socioeconomic backgrounds. Of the students, 21.3% had technical difficulties (ie, unstable connection). One of them said she/he has problems with misunderstanding from parents who required help with housework at the time of the lecture because she/he comes from the countryside. Of the students, 75% were satisfied with the conducted online classes at our department. Onethird found it easier to follow theoretical lectures online. Here are some comments from the students:

Microneedles (MNs) have been manufactured using a variety of methods from a range of materials, but most of them are expensive and time-consuming for screening new designs and making any modifications. Therefore, stereolithography (SLA) has emerged as a promising approach for MN fabrication due to its numerous advantages, including simplicity, low cost, and the ability to manufacture complex geometrical products at any time, including modifications to the original designs. This work aimed to print MNs using SLA technology and investigate the effects of post-printing curing conditions on the mechanical properties of 3D-printed MNs. Solid MNs were designed using CAD software and printed with grey resin (Formlabs, UK) using Form 3 printer (Formlabs, UK). MNs dimensions were 1.2 × 0.4 × 0.05 mm, arranged in 6 rows and 6 columns on a 10 × 10 mm baseplate. MNs were then immersed in an isopropyl alcohol bath to remove unpolymerized resin residues and cured in a UV-A heated chamber (Formlabs, UK). In total, nine samples were taken for each combination of curing temperature (35°C, 50°C, and 70°C) and curing time (5 min, 20 min, and 60 min). Fracture tests were conducted using a hardness apparatus TB24 (Erweka, Germany). MNs were placed on the moving probe of the machine and compressed until fracture. The optimization of the SLA process parameters for improving the strength of MNs was performed using the Taguchi method. The design of experiments was carried out based on the Taguchi L9 orthogonal array. Experimental results showed that the curing temperature has a significant influence on MN strength improvements. Improvement of the MN strength can be achieved by increasing the curing temperature and curing time.

Although homeostasis is a commonly accepted concept, there is incontrovertible evidence that biological processes and functions are variable and that variability occurs in cycles. In order to explain and understand dysregulation, which has not been embraced by homeostatic principles, the allostatic model has emerged as the first serious challenge to homeostasis, going beyond its homeostatic roots. Circadian rhythm is the predominant variation in the body, and it is a pattern according to which many physiological and pathological events occur. As there is strong experimental and clinical evidence that blood pressure fluctuations undergo circadian rhythm, there is equally strong evidence that targeted time therapy for hypertension provides a better outcome of the disease. The research has gone even further throughout the development and approval process for the use of pulsatile drug release systems, which can be considered as an option for an even more convenient dosage regimen of the medicines needed.

Since glaucoma is a serious health problem, numerous therapeutics are being developed to reduce Intraocular Pressure (IOP) as the only modifiable factor of all glaucoma symptoms. IOP-lowering agents are divided into six groups, each of which has a specific mechanism of action and side effects, which are the focus of this article and are explained in detail. All the mentioned agents are formulated as eye drops. However, as conventional topical eye drops have significant disadvantages, of which poor bioavailability and patient noncompliance are the main, novel approaches to designing their drug delivery systems were used and briefly presented in this review. Review Article Rahić et al.; OR, 14(2): 17-33, 2021; Article no.OR.66197 18 Graphical Abstract