System for identifying solid dosage units

A system is described for identifying solid dosage units, such as tablets or capsules, of drugs or other medicaments which may be found beside a patient or which may have been handed in at a hospital. The system comprises a sizing member having a substantially straightsided channel which tapers towards one end to define a V-shaped channel in which a dosage unit can be placed, markings being associated with the channel for indicating a dimension parameter of the unit when so placed. The system also comprises a color region having a plurality of colored areas for indicating a color parameter of the dosage unit, a shape region bearing a series of shape parameters and an information storage and retrieval system which may be in the form of a punched card system or a computer. Parameters of the dosage unit obtained from said V-shaped channel, from said color region and from said shape region, and, optionally, from other physical characteristics of the dosage unit are fed into the information storage and retrieval system to provide an identification of the unit.

BACKGROUND OF THE INVENTION 
This invention relates to a system for identifying solid dosage units, such 
as tablets or capsules, of drugs or other medicaments. 
It is often necessary to be able to identify solid dosage units, such as 
tablets or capsules, of drugs or other medicaments. Even though an 
increasing number of pharmaceutical companies is making attempts to 
identify its products, it is not always possible to print on capsules or 
impress on tablets sufficient information to enable a positive 
identification to be made. Furthermore, printing can become worn and 
impressions eroded so that markings on a dosage unit cannot always be 
relied upon with certainty. 
A proprietary directory includes voluminous tables listing the 
characteristics of solid dosage units on the market. In order to identify 
a dosage unit from these tables, it is necessary to make some fairly 
accurate measurements of the diameter, length and/or thickness of the unit 
and to make subjective decisions as to colour, texture, etc. These 
measurements and decisions may be difficult if the units have become worn 
through abrasion or faded with age or exposure to light. In any case, 
since the tables list some 1500 different dosage units the positive 
identification of a dosage unit can be a lengthy and arduous task. 
The identification of solid dosage units may be required in several 
situations. In one situation, a hospital or area pharmacist may require to 
identify dosage units which are in an unmarked container or have been 
handed in by a member of the public, identification being necessary to 
ascertain whether the dosage units contain dangerous drugs or what may be 
the best method of disposal. This is a nonemergency situation but, 
nevertheless, a time-consuming one. 
Another situation where identification of dosage units may be required is 
where unconsumed dosage units are found beside a patient in cases of 
drug-overdose, self-poisoning or attempted suicide. In these cases there 
is a paramount need for speedy identification of the dosage units on the 
spot so that life-saving measures or antidotes can be applied to the 
patient as soon as possible. Under these circumstances it would be 
desirable for the identification to be made by or under the surveillance 
of ambulance personnel or other persons so that, if necessary, appropriate 
counter-measures can be taken before the patient is moved. 
It is an object of the present invention to provide a system whereby such 
identification can be effected. 
SUMMARY OF THE INVENTION 
According to the present invention there is provided an identification 
system for a solid dosage unit, comprising a member defining a 
substantially straight-sided channel which tapers from one end towards the 
other to define a V-shaped channel in which a dosage unit can be placed, 
markings being associated with the channel for indicating a dimension 
parameter of the unit when placed in the channel, a colour region having a 
plurality of coloured areas for indicating a colour parameter of the 
dosage unit, a shape region bearing a series of shape parameters, and an 
information storage and retrieval system operative, when fed with 
parameters of the dosage unit obtained from said V-shaped channel, from 
said colour region and from said shape region, and, optionally, with other 
physical parameters of said dosage unit, to provide an identification of 
the unit. 
The system is conveniently designed so that an exact match of parameters is 
not required, the nearest parameter being sufficient, so that account can 
be taken of abrasion, fading and the slight variations in dimensions which 
may occur in production. 
It is surprising that, in spite of the number of different types of dosage 
units available, a positive identification can be made in a very short 
time using the present system. Indeed in one demonstration it was possible 
on the basis of five or six parameters to make a positive identification 
in about 30 seconds of a particular dosage unit from 150 dosage units 
including some very similar in appearance to the particular one 
identified. 
Part of the success of the present system is believed to reside in the 
V-shaped channel member or sizing-V. This can be in the form of a solid 
member one face of which is formed with a groove which is V-shaped in plan 
view or two parallel sided walls mounted on a base so as to converge 
towards a point to form a V-shaped channel. Lines are marked across the V, 
normal to the bisector of the angle of the V and equidistant from each 
other. These lines are numbered but the numbering and spacing of the lines 
will be related to the angle of the V and to the information to be held in 
the storage system. At the present moment, we prefer an apex angle for the 
V of about 6.degree.15', a numbering of 0 to 35 and a line spacing of 5 
mm. but these values are not to be regarded as limiting in any way. 
In order to use the sizing-V, it is held with the apex pointing downwards 
and the dosage unit is placed in the channel firstly edge-on and allowed 
to descend as far down the V as it will go. The number of the line next 
below the lower edge of the dosage unit is noted and provides a parameter 
related to the thickness of the unit and referred to herein as the 
"edge-on V number".The unit is then taken out of the V and replaced in the 
channel so as to be seen in plan view. Again the unit is allowed to 
descend as far down the V as it will go and the number of the line next 
below the lower side of the unit is noted to provide a parameter related 
to the diameter or a length dimension of the unit and referred to herein 
as the "plan V number". 
Other parameters for identifying a dosage unit are obtained from the colour 
card which is provided with a number of different colour samples each of 
which is numbered. The dosage unit is compared with the colour samples and 
the number of the sample which is the nearest approximation to the colour 
of the unit is noted as "the colour number". Likewise the card bearing a 
series of shape parameters shows a series of numbered edge-on views and a 
series of plan views of various possible shapes, each view being numbered. 
For example, the plan view may include a circle, a triangle, a rhombus, a 
pentagon, a hexagon, and other polygons with sharp or rounded corners, and 
various ellipses. The dosage unit is viewed edge-on and the edge-on shape 
view on the card nearest to that of the unit is noted to provide a further 
parameter referred to herein as "the edge-on shape number". Likewise 
another parameter for the plan view is also obtained and referred to as 
"the plan shape number". 
Other physical parameters of the dosage unit may be noted which do not 
require measurement, but which can nevertheless be fed to the storage 
system to aid in identification. Thus, for example, an indication as to 
whether the dosage unit is a tablet or capsule can be a first 
identification step which can reduce the number of items to be considered 
under the remaining parameters by the storage and retrieval system. 
Likewise information as to whether the dosage unit is glossy or not may be 
useful. 
Finally, markings on the dosage unit, insofar as they do not provide 
immediate and positive identification may be considered. However, such 
markings should be regarded as confirmatory and will preferably not be 
taken into consideration until a positive identification has been effected 
using the other parameters. 
The various parameter numbers serving to identify the dosage unit are then 
fed to the information storage and retrieval system, where, by a process 
of selection or elimination, information giving a positive identification 
of the dosage unit is provided. If by any chance the storage and retrieval 
system relates the parameters fed into it to more than one type of dosage 
unit, either due to great similarity between the two types (which is a 
possibility) or due to some other reason connected with the reading of the 
parameters (e.g. due to abrasion or fading), markings on the dosage unit 
can provide a final check or a simple physical or chemical test or 
spectroscopic analysis may serve to decide which dosage unit is correct. 
The information storage and retrieval system may take many forms, one 
convenient form being a punched card system. In such a punched card system 
a plurality of edge-punched cards is, for example, stacked edge-on in a 
storage container. Each card carries details of respective dosage unit, 
including name, ingredients, indications, overdose symptoms, overdose 
treatment, analytical data, etc. Each card is punched around its edge with 
holes each of which is associated with a parameter relevant to a dosage 
unit to be identified. Appropriate holes are cut through to the edge of 
the card and the arrangement may be such that when a selector pin is 
passed through an appropriate aperture of each card, for example, the 
aperture corresponding to the colour number 14, all cards other than those 
relating to dosage units of colour number 14 are removed. The process is 
repeated for each parameter in turn until the last remaining card 
identifies the dosage unit. Variations of this selection process are 
possible in accordance with conventional manipulations of punched cards. 
If desired, the punched card information storage and retrieval system may 
be operated in conjunction with a computer, but it may be desirable to use 
a computer for the whole information storage and retrieval system, with 
appropriate memory units for each dosage unit and a selection mechanism 
programmable by punching into it the appropriate parameter numbers to give 
a final read-out of the desired information relating to the selected 
dosage unit in one or several places. It will be appreciated that 
conventional computer systems can be adapted in accordance with the 
requirements of the present invention and they will therefore not be 
described in further detail. For local area or hospital identification 
systems, a punched card information storage and retrieval system is 
probably cheaper, but a computerised system could be cheaper for a 
national system. 
In order for the present identification system to produce optimum results, 
it is designed for the parameters appropriate to a dosage unit to be fed 
to the information storage and retrieval system according to an agreed 
protocol and for the person or personnel operating the identification 
system to be trained and experienced in using the system. The protocol is 
so designed that, for example, an ambulance man at the site of an incident 
and in possession of a dosage unit can telephone an area pharmacist at a 
hospital and in charge of the information storage and retrieval system 
and, by answering a series of questions in accordance with the protocol 
can enable the pharmacist to identify the dosage unit and provide 
information on appropriate counter-measures. 
As just indicated, it is an advantage of the present identification system 
that the dosage unit to be identified does not have to be in the same 
place as the information system. All that is necessary is that the person 
in possession of the dosage unit to be identified must be in possession of 
the sizing-V, the colour card and shape card. These three items are 
conveniently combined as one unit which may be, for example, about the 
size of a cheque book, so that it can be conveniently carried in the 
pocket, and provided with a protective cover or in a protective wallet. 
Thus, the unit may have the form of a front plate formed with two 
upstanding, parallel-sided ribs directed towards each other at one end to 
define a V-shaped channel, and a back plate. A card is printed on one side 
with a series of lines and numbers to give the V number parameters, and 
with a number of edge-on view and plan views of different dosage units, 
each view also having an appropriate number allocated to it. The back of 
the card carries colour samples, also numbered, and the card is sandwiched 
between the two plates, which may be manufactured by an appropriate 
process in optically clear plastics, and accurately located in relation to 
the V-shaped channel. The two plates are secured together by a 
snap-action, adhesive bonding or welding to provide a convenient unit.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to FIGS. 1 to 3, there is shown a combined sizing and 
parameter-generating unit for use in the present identification system. 
The unit comprises a front plate 1 which is manufactured from good quality 
optically-clear plastics and is formed with two upstanding, parallel-sided 
ribs 2 which are directed towards each other at one end to define a 
V-shaped sizing channel 3. The unit also comprises a back plate 4 which is 
also manufactured of the same plastics as the front plate. At their edges, 
the plates 1 and 4 are formed with female and male snap-action fasteners 5 
and 6 respectively so that they can be joined together and the front plate 
1 is formed with locating pins 7 for passing through apertures in a stiff 
card 8 and locating it accurately in relation to the ribs. The card is 
visible through the front plate 1 and as shown in FIG. 1 bears a series of 
numbered graduation lines associated with the sizing channel 3, the apex 
angle of which is about 6.degree.15'. It also bears on its front a series 
of edge-on views numbered 1 to 9 and a series of plan views numbered 1 to 
9. As shown in FIG. 2, the back of the card 8 bears three series of colour 
samples numbered 1 to 18 and legends regarding markings on the dosage 
units according to whether they are tablets or capsules. A set of punched 
cards, of which one is shown in FIGS. 4a and 4b are maintained in a store, 
each bearing information regarding a particular dosage unit. Each card is 
formed with punched apertures around its edge and some of these are cut 
away as indicated at 9. 
In order to illustrate the use of the present identification system, it 
will be assumed that a patient has been discovered in a collapsed state 
and that beside him there are some white scored tablets of the shape shown 
at A and B in FIG. 1. The ambulance man who discovers the patient then 
telephones or makes radio communication with the local area information 
pharmacist who is in charge of the punched card information storage and 
retrieval system. The pharmacist then puts the protocol into operation and 
first asks the ambulance man if he has a tablet or a capsule. The 
ambulance man replies that he has a tablet so the pharmacist inserts a 
selector pin into the stack of punched cards to remove to a separate 
location in the store all those cards relating to capsules, leaving only 
those relating to tablets. 
In response to further questions from the pharmacist in accordance with the 
protocol, the ambulance man gives the colour number (the number 
corresponding to white on the back of the card), the edge-on or elevation 
shape number (1 in this case) and the plan-view number (also 1). The 
ambulance man is then instructed to place the tablet edge-on in the V as 
far down as it will go without force and to give the next number below the 
bottom edge of the tablet. As shown at A in FIG. 1, this edge-on V number 
is 14. Likewise the plan V number is given and is 30. 
After each number corresponding to a parameter of the dosage unit has been 
given the pharmacist repeats the selection procedure until only one card 
is left which identifies the tablet. At this point markings on the tablet 
can be asked for to confirm the identification although there may be 
certain cases where these markings, e.g. scoring, have to be taken into 
consideration in arriving at the identification. 
Experiments have shown that with the present system set up for 150 
different dosage units a positive identification can be made after only 
five or six parameters have been given and in a very short time, which 
depends to some extent upon the skill of the pharmacist or other operator 
of the punched card system, even between dosage units which appear very 
similar to the untrained eye. It is believed that this is due primarily to 
the V-shaped sizing channel and it is surprising that with this channel it 
is possible to show up marked differences between dosage units which are 
apparently very similar. 
It will be appreciated that many variations of the present identification 
system are possible and that apart from sizing in a V-shaped channel other 
parameters may be taken and in different orders. Furthermore, the apex 
angle of the V-shaped channel does not appear to be critical but should be 
such as to show up or amplify small differences between different dosage 
units. In this connection, it is to be noted that as it is the number next 
below the bottom of the dosage unit in the channel which is read, the 
channel can accommodate slight variations in thickness and diameter such 
as occur in the manufacture of dosage units. Likewise the colour samples 
are chosen to be representative of ranges of colours and an exact colour 
match is not required, only the best colour approximation being required. 
This will usually accommodate for any fading of colour due to exposure to 
light. In this connection, it is to be appreciated that the operator of 
the sizing unit should not be colour blind. 
Finally, it will be appreciated that many variations of the information, 
storage and retrieval system may be made. If there is a very large number 
of cards then it may be desirable to store them in a plurality of storage 
units under a plurality of headings, e.g. "tablets--white or coloured", 
"capsules--hard or soft". Furthermore, as also indicated the information 
storage and retrieval system can be in the form of a computer with a 
keyboard. When the ambulance man or like reads out the parameter numbers, 
the computer operator can punch them out on the keyboard and feed 
appropriate information to the computer which will in known manner make 
the appropriate selection from its memory banks to produce a read-out or 
visual display of the information relevant to the dosage unit.