A) Optimal Medication Monitor(s) and Method of Retrieving Adherence Record.
B) Other Dose Removal Monitors.
Stack Type Medication Monitor for Global Drug Facility Packages
- One Stack Monitor for Both the Four Drug Combination Caplet and the Two Drug Combination Tablet Produced by WHO’s Global Drug Facility, (GDF)
If different dispensers were used for the initial phase of therapy and for the continuation phase of therapy, as suggested on the previous page, clinics would need to maintain an excess inventory of monitors because the relative number of patients who are in the initial phase of therapy and in the continuation phase can vary. Also, the use of separate monitors for the two phases of therapy could require transferring patient information from one monitor to another when a patient started the continuation phase. So, it would be desirable if one monitor could dispense both the four drug combination caplets used in the initial phase of therapy and the two drug combination tablets used in the continuation phase.
The dispenser shown in Figure 8 is similar to that shown in Figures 1 - 6 on the previous page except that its side cover can be installed in two ways for dispensing strips of packages having two different thicknesses. In this Figure, the dispenser is configured to dispense the four drug combination caplet for the initial phase of therapy.
Since the package for the two drug combination tablet used in the continuation phase of therapy is thinner than the package for the four drug combination caplets, the height of the exit opening needs to be reduced to dispense these packages. To establish the proper exit opening for dispensing the thinner packages, the side cover is removed, turned over end-for-end, and reinstalled in the dispenser.
Figure 9 shows the side cover in both positions, as it would be viewed from the outside of the dispenser and illustrates how installing it in one orientation or the other changes the height of the exit opening.
In Figure 9, note that the opaque portion of the side cover is red on one side and green on the other. These colors correspond to the colors of the medication packages. So, when the caregiver installs the side cover, it is installed so that the color of the opaque portion of the cover which is visible matches the color of the package to be dispensed.
While inverting the side cover configures the dispenser for different thicknesses of packages, it does not adjust for their different widths. One way of adapting the narrower strips to be dispensed in this dispenser would be to use adapters as shown in Figure 10.
Since the encoder which senses the height of the stack of strips of medication packages (see previous page) will indicate a different change in stack height when a strip of thick packages is removed than when a strip of thin packages is removed, there needs to be a way of informing the microcontroller which type of package is being removed. As shown in Figure 9, the upper end of the side cover extends higher when the four drug combination packages are being dispensed than when the two drug combination packages are being dispensed. So, it is simple for a switch to detect which type of medication the dispenser is configured to dispense. Figure 13 shows how an inexpensive tactile switch mounted on the monitor’s circuit board could be used for this purpose by employing a lever to actuate the switch.
The adapter shown in Figure 10 would be sized so that it was (1) the same width as strips of packages of the four drug combination caplets, (2) the same length as a strip of five packages of the four drug combination caplets, and (3) the same thickness as the strips of packages of the two drug combination tablets. This one adapter would be suitable for strips of 2, 3, 4, or 5 packages of the two drug combination tablets.
Figure 11 shows the dispenser configured to dispense strips of packages of the two drug combination tablets with adapters.
Having a lever to actuate the switch, as shown, offers several advantages relative to using a switch whose button contacts the side cover directly: (1) The lever intrudes only a small distance into the medication compartment at a location where it does not interfere with either the stack of packages or the compression plate. (2) In actuating the switch the contact tip of the lever moves further than the switch button, thus reducing the need for precision in the location of the switch. (3) Mounting the switch on the circuit board eliminates the cost of switch wiring and switch mounting hardware which more than offsets the cost of the lever itself.
Since the switch lever is light weight, and pivots freely, it would only act to overcome the switch operating force when its tip is in contact with the side cover. So, there is no need for the switch lever to have a separate spring. Because the switch lever intrudes into the path of the side cover when the side cover is installed, its contact end is rounded to permit the lever to be pushed back as the side cover is slid into position and the excursion of the switch lever is limited by a slot in a wall of the medication compartment, as shown in Figure 13.
Figure 14 shows an overall view of the dispenser with its top and side covers removed. This shows the location of the switch lever in relation to other features of the dispenser.
As with the dispensers described on the previous page, removal of the side cover provides the caregiver with access to a Caregiver’s Button which can be used to display the adherence record on the matrix display, as described in the section Using a Dot Matrix Display to Retrieve the Adherence Record, a USB connector which can be used to transfer data to or from a host computer, the monitor’s batteries, and the medication compartment into which medication can be loaded. Figure 15 also illustrates these features.
As the dispenser box is currently envisioned, the space above the side cover lies behind a skirt on the end of the top cover. This skirt also holds the side cover in position. So, when the side cover is to be removed, it is necessary to first remove the top cover, as shown in Figure 15.
When the dispenser is assembled, the top cover would be held in place by a latch or lock. Thus, before the top cover could be removed, it would need to be unlatched, as indicated in Figure 15.
A suitable latch or lock should meet several criteria:
1) The latch should engage automatically when the top cover is installed.
2) It should be relatively easy for the caregiver to release the latch without a key or other device which is not part of the dispenser and could be lost.
3) It should be difficult for anyone other than the caregiver to release the latch so there would be some level of security for the medication and batteries.
4) The latch should not significantly increase the cost of the dispenser.
Since we are continuing to evaluate possible mechanism for the latch, no latch mechanism is presented here.