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Oral medications are not readily available for a subset of the population, including pediatric patients, patients with comorbidities, and patients on a tapering schedule. Additive manufacturing (AM) provides a viable solution to this shortcoming in current medication standards, allowing for tailored oral dosage forms. Two methods, semisolid extrusion (SSE) and selective laser sintering (SLS) show particular promise for this application and are used in this thesis. SSE has particular applicability for clinical applications, while SLS has shown an aptitude for creating an array of doses of medication at a larger scale. 

Investigation into printing oral dosage forms using SSE in a hospital setting showed promising results. Oral dosage forms were created with consistency from batch-to-batch in mass and drug content. The drug content achieved, additionally, aligned closely to the desired drug content. Interviews with pharmaceutical professionals yielded information leading to a suggested workflow overhaul, utilizing SSE, for implementation in hospitals. 

Further investigation into SSE led to the development and printing of oral dosage forms on a tapering schedule. These oral dosage forms were examined with image analysis using a machine learning model (MLM). This added a layer of validation, where there is typically no validation to dose-adjusted and unlicensed medication. MLMs were able to determine differences in the images and classify images with a high-degree of success, particularly with the use of more than one viewpoint of the oral dosage forms.

The impact of geometry on the fundamental properties of SLS oral dosage forms was next studied. It was found that geometry, with shape and surface-area-to-volume ratio (SA/V) have an impact on not just the dissolution profile of the oral dosage forms, but also the resultant print quality of the oral dosage forms in terms of mass and volume compared to the theoretical values. 

Analysis into different polymers and polymer grades was performed for SLS oral dosage forms. The findings indicated that the type of polymer and polymer grade impact the resultant oral dosage forms. A general trend of slower laser sintering and higher printing temperatures, within an appropriate printing window for the material, yielded oral dosage forms that best adhered to European Pharmacopoeia guidelines.

Overall, SSE and SLS have shown distinct advantages for pharmaceutical application. The outcomes demonstrated in this work indicate the viability of SSE, particularly with image analysis validation, in a clinical setting. This work has also shown that properties such as geometry and polymer choice have a large impact on SLS printing.