Although no published data exist on the use of albuterol by mouth or inhaler during lactation, data from the related drug, terbutaline, indicate that very little is expected to be excreted into breastmilk.[1] The authors of several reviews and an expert panel agree that use of inhaled bronchodilators is acceptable during breastfeeding because of the low bioavailability and maternal serum levels after use.[2][3][4][5][6]

The reformulation of suspension-based pressurized metered dose inhalers (pMDI) with low global warming potential (GWP) propellants is challenged by wide-ranging changes to their chemicophysical properties such as vapor pressure, density and latent heat. The effect of low-GWP propellants on spray pattern and plume geometry for suspension pMDIs are not fully understood. There is a lack of data regarding the role of propellant choice and potential interactions with suspended drugs, which may explain performance variations between products and guide development of in-silico models. In this study, high speed imaging was used to measure the plume morphology and optical density of sprays containing HFA134a, HFA152a and HFO1234ze(E) propellants. Propellant-only placebo controls were compared to suspension formulations containing 2 mg/mL salbutamol sulphate. It was found that the presence of suspended particles has a significant effect on plume structure, reducing correlations between propellant thermophysical properties and cone angle, targeting angle, and optical center of mass by 6-7 times. These effects vary depending on propellant type due to variations in flash-evaporation behavior, which is less pronounced in low-GWP propellants compared to HFA134a. HFA152a sprays have a 23% reduction in Jakob number compared to HFA134a; plume width at the mouthpiece exit is commensurately increased by 40%. Equivalent HFO1234ze(E) sprays have less pronounced differences in Jakob number (13% reduced) and plume width (25% increased) compared to equivalent HFA134a sprays. Empirical models and standards which implicitly incorporate the flash-evaporation effects commonly observed in high-GWP HFA propellants may require adjustment to be suitable for use with low-GWP formulations.

The surge in COVID-19 cases during the 2020 Spring led to a nationwide shortage of albuterol inhalers. As a new surge has begun, shortages may make it difficult for patients with obstructive lung disease, including children with asthma, to obtain refills. Since there is no evidence that albuterol relieves symptoms in COVID-19 patients with respiratory symptoms not caused by bronchospasm, it is reasonable for clinicians to not prescribe it for COVID-19 patients unless they also have asthma or chronic obstructive pulmonary disease.

BACKGROUND Asthma is a common disease in the U.S.

Although high-speed laser imaging is the current standard to characterize the plume angle of suspension-based pressurized metered dose inhalers (pMDIs), this method is limited by the inability to identify the drug content in a droplet and simulate inhalation flow. The Plume Induction Port Evaluator (PIPE) is a modified induction port for cascade impactors that allows for the calculation of the angle of a plume based on direct drug mass quantification rather than indirect droplet illumination under airflow conditions. The objective of this study was to investigate the use of the PIPE apparatus to evaluate the effect of airflow on the Mass Median Plume Angle (MMPA) of commercially available suspension-based pMDIs (Ventolin® HFA, ProAir® HFA, and Proventil® HFA). Deposition patterns within PIPE were log-normally distributed allowing for the calculation of the MMPA for the three suspension products. Mass-based plume angles were significantly smaller (narrower angle) when inhalation airflow was used compared to no flow conditions (reduction of MMPA was 8, 16, and 13% for Ventolin® HFA, ProAir® HFA, and Proventil® HFA, respectively). Additionally, new parameters for characterizing plume geometry were calculated (MMPA ex-actuator and plume orientation). Mass-based plume angles of the suspension-based pMDI formulations were highly reproducible and demonstrated the effect of inhalation flow rate. These results suggest that plume geometry tests should be evaluated under flow conditions which is not possible using current methodologies. Graphical Abstract ᅟ.

The performance of pressurized metered dose inhalers (MDIs) is affected by formulation and device variables that impact delivered dose, aerodynamic particle size distribution, and consequently lung deposition and therapeutic effect. Specific formulation variables of relevance to two commercially available products-Proventil® HFA [albuterol sulfate (AS) suspension] and Qvar® [beclomethasone dipropionate (BDP) solution]-were evaluated to determine their influence on key performance attributes measured experimentally with in vitro cascade impaction studies. These commercial MDIs, utilized as model systems, provided mid-points for a design of experiments (DoE) plan to manufacture multiple suspension and solution MDI formulations. The experimental results were utilized as input variables in a computational dosimetry model to predict the effects of MDI formulation variables on lung deposition. For the BDP solution DoE MDIs, increased concentrations of surfactant oleic acid (0-2% w/w) increased lung deposition from 24 to 46%, whereas changes in concentration of the cosolvent ethanol (7-9% w/w) had no effect on lung deposition. For the AS suspension DoE MDIs, changes in oleic acid concentration (0.005-0.25% w/w) did not have significant effects on lung deposition, whereas lung deposition decreased from 48 to 26% as ethanol concentration increased from 2 to 20% w/w, and changes in micronized drug volumetric median particle size distribution (X50, 1.4-2.5 μm) increased deposition in the tracheobronchial airways from 5 to 11%. A direct correlation was observed between fine particle fraction and predicted lung deposition. These results demonstrate the value of using dosimetry models to further explore relationships between performance variables and lung deposition.