What type of drug release system achieves a slow release of drug over an extended period?

The choice of a sustained release system is indeed the correct answer for a drug release system designed to achieve a slow release of a drug over an extended period.

Sustained release formulations are specifically designed to maintain therapeutic drug levels in the bloodstream for a prolonged time, compared to immediate release formulations that release the entire dose rapidly, leading to a quick peak in drug concentration and then a significant decline. By contrast, sustained release systems can employ various mechanisms such as polymer matrices or encapsulation techniques that allow the drug to be released at a controlled rate, thereby reducing the frequency of dosing and improving patient compliance.

This type of release is crucial for medications that require consistent plasma concentrations to be effective, such as in the management of chronic conditions where stable levels can avoid fluctuations that might cause toxicity or subtherapeutic effects. Sustainable release technologies aim to minimize side effects and improve the overall therapeutic outcomes by ensuring that the medication remains effective over an extended timeframe without requiring multiple doses throughout the day.