Rectal Drug Delivery to Paediatric Population

Despite its unpopularity, the rectal route of paediatric drug administration remains of interest especially in pre-school children as it can overcome some drug delivery challenges with oral and parenteral routes. Few studies have been conducted on the use and acceptability of traditional rectal dosage forms (i.e., suppositories, enemas and gels) in different parts of the world. It showed that barrier to adoption could be linked with poor knowledge, little information and understanding of this administration modality. Reformulation for the rectal delivery of drugs intended for oral and/or parenteral administration that do not reach their full potential, was explored by a study at University College London. The top 3 candidates were Azithromycin, Amodiaquine and Raltegravir. Little rectal delivery innovation has occurred but topics such as acceptability and use of rectal drug delivery; types of rectal dosage forms and reformulation considerations are discussed presently in order to raise awareness around the need to modernise rectal dosage forms this to achieve the full potential for successful reformulation.

Achievements in Thermosensitive Gelling Systems for Rectal Administration

Rectal drug delivery is an effective alternative to oral and parenteral treatments. This route allows for both local and systemic drug therapy. Traditional rectal dosage formulations have historically been used for localised treatments, including laxatives, hemorrhoid therapy and antipyretics. However, this form of drug dosage often feels alien and uncomfortable to a patient, encouraging refusal. The limitations of conventional solid suppositories can be overcome by creating a thermosensitive liquid suppository. Unfortunately, there are currently only a few studies describing their use in therapy. However, recent trends indicate an increase in the development of this modern therapeutic system. This review introduces a novel rectal drug delivery system with the goal of summarising recent developments in thermosensitive liquid suppositories for analgesic, anticancer, antiemetic, antihypertensive, psychiatric, antiallergic, anaesthetic, antimalarial drugs and insulin. The report also presents the impact of various types of components and their concentration on the properties of this rectal dosage form. Further research into such formulations is certainly needed in order to meet the high demand for modern, efficient rectal gelling systems. Continued research and development in this field would undoubtedly further reveal the hidden potential of rectal drug delivery systems.

F FORMULATION DEVELOPMENT AND EVALUATION OF CARBOPOL-INCORPORATED THERMOREVERSIBLE GELS OF PSEUDOEPHEDRINE FOR RECTAL DRUG DELIVERY

Objectives: The present study describes the preparation and evaluation of a Poloxamer 188 (P188)-based thermoreversible gel using Carbopol 934P (C934P) as a mucoadhesive polymer of pseudoephedrine for enhancing the bioavailability and to avoid the first-pass metabolism. Materials and Methods: Five formulations (F1-F5) were prepared using cold method. The prepared gels were characterized by pH, drug content, spreadability, mucoadhesive force, gelation temperature, and drug release profile. Thermoreversibility of P188/C934P gel was demonstrated by rheological studies. The drug-polymer compatibility was studied using Fourier transform infrared (FTIR). Results: The incorporation of carbopol into P188 gel also reduced the amounts of drug released from the gel formulations. FT-IR studies revealed that there are no interactions between the drug and polymers. Drug content of gels was estimated and the results were found to be satisfactory. In vitro dissolution studies revealed a good drug release from the gels. The drug release was higher in formulations F4 and F5 and lower in F1, F2, and F3 formulations. The order of drug release was found to be F5>F4>F3>F2>F1. Conclusion: These findings suggested that developed thermoreversible gels could be used as promising dosage forms to rectal drug delivery for prolonged periods in the management of hemorrhoids.