Poorly Soluble Drugs with Low Bioavailability
Drugs with poor water solubility present significant challenges in formulation, often resulting in slow onset of action and low oral bioavailability. Previously, these issues were typically addressed by encapsulating the drugs in soft capsules or micronizing them. Now, liquid-filled capsule technology allows for the creation of solutions, suspensions, microemulsions, or molten contents using suitable solvents or carriers. For example, digoxin and cyclosporine can be formulated into oil solutions, and nifedipine into PEG (polyethylene glycol) 6000 melts, which are then filled into liquid-filled capsules using specialized equipment, conveniently solving the absorption problem.
Low-Melting-Point Drugs
Drugs with low melting points or those that are liquid at room temperature are difficult to formulate into solid powders, often requiring the addition of large amounts of excipients. The high temperature and pressure during tablet manufacturing also affect compounds with low melting points. Liquid-filled capsules simplify the manufacturing process.
Ibuprofen, guaiacyl ether, oily vitamins, and a wide range of liquid natural health products, including saw palmetto oil, pumpkin seed oil, linseed oil squalene, garlic oil, ginger oil, and various other liquid or semi-liquid natural plant extracts, can all benefit from this technology.
Low-dose or high-potency drugs
The two main challenges for these drugs are achieving acceptable content uniformity and controlling cross-contamination while ensuring effective worker protection. Liquid filling operations can control volume variation to within 1%, therefore, liquid-filled capsules containing drug solutions can ensure good content uniformity for low-dose drugs such as vitamin D and its derivatives, diphenoxylate, and coenzyme Q10. The technology of liquefying hormones and cytotoxic drugs and then filling them into liquid-filled capsules can reduce dust pollution and harm to employees during solid dosage form manufacturing, making the production process safer.
