Components with relatively high loading of active pharmaceutical ingredients are generally provided. In some embodiments, the component (e.g., a tissue interfacing component) comprises a solid therapeutic agent and a supporting material such that the solid therapeutic agent is present in the component in an amount of greater than or equal to 10 wt % versus the total weight of the tissue interfacing component. Such tissue-interfacing components may be useful for delivery of API doses e.g., to a subject. Advantageously, in some embodiments, the reduction of volume required to deliver the required API dose as compared to a liquid formulation permits the creation of solid needle delivery systems for a wide variety of drugs in a variety of places/tissues (e.g., tongue, GI mucosal tissue, skin) and/or reduces and/or eliminates the application of an external force in order to inject a drug solution through the small opening in the needle. In some cases, a physiologically relevant dose may be present in a single tissue interfacing component.