Pharmacokinetics of Dual Amino Acids for Dry Powder Inhalation Therapy in Pulmonary Drug Delivery: An In-Vivo Study

Smoking cigarettes leads to serious health problems, and addiction is a major concern. De-addiction therapy includes e-cigarettes and counseling, and the success rate is poor in these approaches, warranting alternate therapeutic interventions. The present study evaluates dry powder inhalation using amino acids as a new method.

A novel formulation was prepared using nanospray drying and ball milling techniques. SEM analysis was conducted to ascertain particle size, and pharmacokinetic assessment was done to evaluate how rapidly the drug is released from the formulation. The optimized ratio of ingredients revealed the best formula, L-tyrosine, L-tryptophan, and lactose in the ratio of 5 mg:1 mg: 4 mg, which led to the dry powder preparation. SEM analysis revealed that the dry powder comprising L-tryptophan and L-tyrosine had undergone micronization to 2-4 µm.

An innovative treatment, such as an inhalation powder therapy comprising amino acids, can help reduce mood changes. Depletion of tryptophan to kynurenine controls mood changes, and maintaining a steady tryptophan concentration is expected to help overcome mood changes that trigger smoking recurrence. The microparticles produced by spray-drying were confirmed to include loose agglomerates, which are amenable to inhalation and free dispersion. In-vivo studies revealed that drug action is quick with drug delivery and retention at the site of action.

The synergistic effect of the novel formulation's sustained concentration of tryptophan and tyrosine and inhibition of AChE could diminish the recurrence of smoking. Dry powder inhalation of the formulated drug offers a new and strong method of drug delivery to the alveolus, making it a convenient route of administration that could be superior to other modes of administration in smoking cessation.