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Continuous manufacturing has been promoted as a transformative alternative to batch pharmaceutical production because it can reduce equipment footprint, shorten development-to-commercialisation timelines, and enable more responsive quality assurance. Its appeal rests on the idea that material flows through an integrated process rather than waiting in isolated unit operations. Yet the technical maturity required to make that flow reliable is often understated. The central problem is that continuous operation is sometimes treated as intrinsically superior to batch production, as though continuity alone guarantees better quality. In practice, quality depends on the ability of sensors, models, actuators, supervisory logic, and operators to detect and correct deviations fast enough to prevent poor material from propagating through the line. Without that control capability, continuous systems may amplify rather than resolve process vulnerability. This critical review examines continuous pharmaceutical manufacturing through three linked lenses: control architecture design, process robustness, and regulatory translation. It asks whether current systems are sufficiently controlled to justify claims of superior quality, whether robustness is assessed with appropriate metrics, and whether regulatory frameworks have matured enough to support dynamic manufacturing strategies. The review deliberately treats continuous manufacturing as a socio-technical system rather than as a purely technological upgrade. The evidence indicates that continuous manufacturing has advanced substantially, particularly in direct compression, wet granulation, process analytical technology, residence-time modelling, soft sensing, and model predictive control. However, many demonstrations remain limited by narrow disturbance scenarios, incomplete treatment of start-up and shutdown, uncertain model maintenance requirements, and uneven translation into routine good manufacturing practice. Regulatory acceptance is progressing, but unresolved questions remain around batch definition, traceability, adaptive control validation, and lifecycle change management. The review concludes that continuous manufacturing is not an automatic guarantor of pharmaceutical quality. Its value depends on control-centric process design, standardised robustness assessment, credible digital and analytical infrastructure, and regulatory alignment that recognises dynamic process operation. The future pathway requires stronger pre-competitive collaboration, more realistic stress testing, and regulatory science that keeps pace with advanced control strategies.

The pharmaceutical industry is a significant contributor to environmental pollution, yet the sustainability of pharmaceutical technologies themselves has received less sustained attention than clinical efficacy, quality assurance, manufacturability, and cost. Pharmaceutical products are commonly evaluated through therapeutic performance and regulatory compliance, while the material, energy, solvent, water, packaging, and waste implications of their production and disposal remain secondary. This imbalance is no longer defensible as medicines become embedded within wider debates on planetary health, industrial decarbonisation, chemical pollution, and responsible innovation. Current pharmaceutical technology paradigms often depend on linear manufacturing models in which raw materials, solvents, excipients, packaging components, and delivery devices move through production and use before entering waste streams. This model is particularly problematic where complex formulations, multi-material packaging, single-use components, and persistent active substances create environmental burdens that are difficult to recover or neutralise. The problem is not only the presence of pharmaceuticals in the environment, but also the technological logic that normalises excess material throughput as an acceptable cost of product performance. This critical review examines sustainable pharmaceutical technologies through three connected lenses: green manufacturing, excipient burden, and circular design principles. Green manufacturing addresses how pharmaceutical products are synthesised, processed, purified, and scaled. Excipient burden focuses on the hidden environmental and functional load created by supposedly inactive formulation ingredients. Circular design principles extend the discussion beyond production efficiency toward products, packaging, and delivery systems designed for reduction, recovery, reuse, and responsible end-of-life management. The review identifies that continuous manufacturing, flow chemistry, process intensification, biocatalysis, solvent reduction, process mass intensity, and life-cycle assessment provide important but incomplete routes toward greener pharmaceutical production. It also shows that excipients, packaging, and drug delivery systems remain under-theorised in sustainability debates despite their cumulative contribution to material intensity, environmental persistence, and disposal complexity. Five tables present green manufacturing technologies, excipient burden data, circular design principles, environmental risks, and implementation barriers. The central conclusion is that sustainable pharmaceutical technology requires a systems-level transition rather than a collection of isolated green substitutions. Genuine sustainability will depend on integrating green manufacturing with excipient stewardship, circular product design, environmental risk reduction, regulatory adaptation, and cross-sector accountability. The field must therefore move from sustainability as a supplementary efficiency concern toward sustainability as a core design principle of pharmaceutical innovation.