Nanotechnology approaches for pain therapy through transdermal drug delivery

Abstract

The paper focuses on the advances in the field of pain treatment by transdermal delivery of specific drugs. Starting from a short description of the skin barrier, the pharmacodynamics and pharmacokinetics including absorption, distribution, action mechanism, metabolism and toxicity, aspects related to the use of pain therapy drugs are further discussed. Most recent results on topical anesthetic agents as well as the methods proved to overcome the skin barrier and to provide efficient delivery of the drug are also discussed. The present review is proposing to summarize the recent literature on the pharmacotherapeutic principles of local anesthetics and non-steroidal anti-inflammatory drugs, generally used to alleviate pain but also the drugs as nanoformulations with potential applications in transdermal delivery. A special attention is given to efficient formulations meant for transdermal penetration enhancement of anesthetics where the drug is encapsulated into macrocyclic molecules (cyclodextrins, cyclodextrin derivatives), liposomes or polymer nanoparticles and hydrogels.

A novel local anesthetic system: transcriptional transactivator peptide-decorated nanocarriers for skin delivery of ropivacaine

“…Polymeric nanoparticles for the delivery of LAs via the skin bring a lot of advantages such as delivering the local drug continuously and reducing systemic adverse reactions 34. TAT can successfully enhance the transepidermal absorption of therapeutic molecules for the local therapy.…”

Advanced Analgesic Drug Delivery and Nanobiotechnology

“…Applications of liposomes include transdermal drug delivery, reduced-toxicity antibiotic delivery, ophthalmic delivery, and treatment of parasitic infections [8, 11]. Liposomes are considered reliable drug carriers due to a number of advantages (Table 2) [3]. …”

“…A major advantage of liposomal formulations of local anesthetics is the slow release and subsequent prolonged analgesic effect, while also keeping anesthetic serum levels nontoxic [3, 40]. A number of clinical studies have been conducted to compare free drug solutions with liposomal formulations of local anesthetics.…”

“…The flexible hydrophobic surface of polymers allows them to intercalate between the stratum corneum cells, causing a disruption in lipids, and facilitating drug passage through the skin [3]. Biodegradable polymers release drugs either by erosion or diffusion.…”

“…The transdermal route also offers a convenient mode of drug administration over an extended period of time, particularly in pain medicine, with an increased safety profile for drugs with a narrow therapeutic window [1, 2]. The primary goal of transdermal drug administration is to overcome the skin absorption barrier [3]. Nanotechnology offers a novel method of enhanced dermal penetration for small-size molecules conferring a large specific delivery profile [2].…”