Monitored dosage systems

Requiring patients to produce containers when they attend the doctor, who counts the tablets, seems to do little more than show the patient that the doctor cares about the matter (which is useful) and a tablet absent from a container has not necessarily entered the patient s body. On the other hand, although patients are known to practise deliberate deception, to maintain effective deception successfully over long periods requires more effort than most patients are likely to make. The same applies to the use of monitored-dosage systems (e.g. compartmented boxes) as memory aids and to electronic containers that record times of opeiring. 

Packs for the elderly, including monitored dosage systems... 

Since the monitored dosage systems conflict somewhat with the OPD concept (a pharmacist does not like transferring products from blisters and strips) there may still be a need for a bulk pack, particularly if the use of these dosage systems continues to expand. 

Most controlled release dosage forms administer dmg according to thek design, whether conceptually simple, eg, a fixed release rate for a fixed amount of time, or complex, eg, several different rates for different amounts of time. Alternatively, closed-loop systems contain a sensor to monitor dmg concentration or to administer dmg according to a biological need (11). 

Operation When operated correctly, thickeners require a minimum of attention and, if the feed characteristics do not change radically, can be expected to maintain design performance consistently. In this regard, it is usually desirable to monitor feed and underflow rates and sonds concentrations, flocculant dosage rate, and pulp interface level, preferably with dependable instrumentation systems. Process variations are then easily handled by changing the principal operating controls—underflow rate and floccirlant dose—to maintain stability. 

Tablets were a viable dosage form well before William Brockendon s patent for a tablet machine in 1843. His invention only made them easier to produce. As tablet presses and production-monitoring systems developed,...

The results of this study clearly show the complex dependence of the flocculation process on polymer dosage and charge density. It is seen that the form of dependence varies markedly among the responses monitored. In addition to the factors studied here, it can also be expected to depend upon several other physicochemical conditions of the system, including the type of mixing. The final state of flocculation achieved by a mineral/polymer system will depend upon many interactions in the system as determined by various chemical and hydrodynamic properties of the particles, polymer, dissolved organics and the fluids. 

One approach to the study of solubility is to evaluate the time dependence of the solubilization process, such as is conducted in the dissolution testing of dosage forms [70], In this work, the amount of drug substance that becomes dissolved per unit time under standard conditions is followed. Within the accepted model for pharmaceutical dissolution, the rate-limiting step is the transport of solute away from the interfacial layer at the dissolving solid into the bulk solution. To measure the intrinsic dissolution rate of a drug, the compound is normally compressed into a special die to a condition of zero porosity. The system is immersed into the solvent reservoir, and the concentration monitored as a function of time. Use of this procedure yields a dissolution rate parameter that is intrinsic to the compound under study and that is considered an important parameter in the preformulation process. A critical evaluation of the intrinsic dissolution methodology and interpretation is available [71]. 

For a liquid or semi-solid pharmaceutical dosage form, it is crucial to include a preservative in the formulation. Commonly used preservatives in these systems include sodium benzoate, EDTA, sorbic acid, and parabens. A generic HPLC method is also recommended for the preservatives used in liquid formulations for routine monitoring to ensure the stability of the preservative itself and it must be validated specific to its use with the dosage form. (See chapters on Sample Preparation and Method Development.)... 

P-450 system Monitoring of circulating cyclosporine levels and appropriate dosage adjustment are essential when drugs that affect hepatic microsomal enzymes, particularly the cytochrome P-450 3A enzymes, are used concomitantly (eg, HIV protease inhibitors, anticonvulsants, azole antifungals). 

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