The design and development of controlled-release drug-delivery systems have been
ID: 937579 • Letter: T
Question
The design and development of controlled-release drug-delivery systems have been traditionally used to extend a product's lifecycle. Treatment of many diseases requires a dosage regimen that delivers acceptable therapeutic concentrations of the drug at the site of action, which can be attained immediately and then constantly maintained over the desired duration of treatment. The number of compounds formulated into controlled-release systems are increasing because of their added value and well-recognized advantages such as improved systemic bioavailability, more favorable pharmacokinetic profiles (e g., the maintenance of drug levels within a desired range without exposing patients to potentially toxic or subtherapeutic levels), reduced side effects, and better patient compliance among others. One such formulation (drug dosage form) is shown below. This formulation is used for hypertension, angina, allergies, diabetes and others. Explain how this newest form of drug formulation uses chemical properties' to continually deliver a drug to the body.Explanation / Answer
Let we discuss this interesting drug in two steps of Saline and Membrane
Saline (NaCl Solution) + Drug
The advantage of using saline solution in drug delivery helps in replenishment of electrolyte in the body which also enhances the electrolyte movement responsible for drug delivery as electrolyte acts as transporter of active drugs.
Membrane
The benefit is of combined use of impermeable and semi-permeable membrane.
Impermeable membrane wont allow saline to react with drug {note if saline reacts with drug an free radical forms as precursor other unwanted reactions in the body namely side efffects}
Semi-permeable is important as other membrane will not be helpful in controlled release of saline in a time bound manner. The other advantage of semi-permeable is of movement of saine from capsule to an system {GI tract} and opposite movment is not possible which makes an favored choice of semi-permeable for saline controlled release.