US 5,299,121 AGrant
Non-Prescription Drug Medication Screening System
Issue Date:1994-03-29
•4 Claims
•11 Drawing Sheets
Abstract
A system for use in pharmacies which uses customer inputs to assist the customer with the selection of an appropriate non-prescription medication to relieve symptoms of an illness, injury or the like. The system uses an expert system to perform the selection. The system utilizes a personal computer with a keyboard, monitor and disk drive as input/output devices with appropriate programming for prompting a user to input information which is used by a knowledgebase to determine non-prescription medications which may be purchased by the customer to relieve symptoms of injuries and illnesses covered by the knowledgebase. The system operates by prompting a user at typically a customer in a pharmacy to input basic customer information. After the basic customer information has been input the customer is prompted to select one main symptom category from a list displayed and the choice made results in the appropriate knowledgebase being loaded for the next step. The logic of the loaded knowledgebase itself determines which questions are asked of the customer by the display of appropriate questions on the monitor. The output of each knowledgebase on completion of the questions and answers is a list of component medications recommended for use with the symptoms described. The list of component medications generated by the execution of the knowledgebase is used to search a database to find the appropriate product to be recommended.
Metadata
Assignee
- Medscreen, Inc.
Inventors
- Albert R. Brill
- Denis Sosnoski
Application Information
Application Number:US 8936528
Filing Date:1992-06-04
Priority Date:1992-06-04
Art Unit:231
Classifications
IPC:
G06F 1542
Field of Search:
364395413.01;413.02;400;401924
Patent Drawings (11 sheets)
Description
SUMMARY OF THE INVENTION
The invention is a system for use in pharmacies which uses customer inputs to assist the customer with the selection of an appropriate non-prescription medication to relieve symptoms of an illness, injury or the like. The system uses an expert system to perform the selection and thereby free-up the time of the pharmacists to the extent that customers are able to obtain information and suggestions for non-prescription medications which they would otherwise obtain from the pharmacists. In this manner, by reducing the amount of time needed by the pharmacists to answer customer questions relating to non-prescription medications, the pharmacists are able to devote more time to the filling of prescriptions and other required tasks.
The system utilizes a personal computer with a keyboard, monitor and disk drive as input/output devices with appropriate programming for prompting a user to input information which is used by a knowledgebase to determine non-prescription medications which may be purchased by the customer to relieve symptoms of injuries and illnesses covered by the knowledgebase. The system incorporates six main sections as follows:
1. Input Customer Information
2. Select Main Symptom
3. Execute Symptom Knowledgebase
4. Select Product Recommendation
5. Generate Session Report
6. Close Session
The system operates by prompting a user, typically a customer in a pharmacy, to input basic customer information such as the customer name, gender, and date of birth. After the basic customer information has been input, the customer is prompted to select one main symptom category from a list displayed. Each category corresponds to a separate knowledgebase, and the choice made results in the appropriate knowledgebase being loaded for the next step.
Once the knowledgebase for the selected main symptom has been loaded, it begins its execution. The logic of the knowledgebase itself determines which questions are asked of the customer by the display of appropriate questions on the monitor. The customer answers each question, as appropriate.
The output of each knowledgebase on completion of the questions and answers is a list of component medications recommended for use with the symptoms described. The list of component medications generated by the execution of the knowledgebase is used to search a database to find the appropriate product to be recommended. After selecting the first product to be recommended, the component medications present in this product are removed from the list of recommended component medications. If any component medications remain in the resulting list, another product is selected in the same way. This continues until each component medication recommended by the knowledgebase is present in one and only one recommended product.
Once the recommended product or products have been determined, a session report for the customer is generated, which may be printed immediately or queued for later printing. The actual product recommendations follow the session summary. For each recommended product, a session report is printed with the product name and a summary of usage information for the product. This information may include warnings and usage restrictions as well as actual directions for use.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overview of the invented system in flow chart form.
FIG. 2a-2e is flow chart showing the execution of a knowledgebase for cough and cold symptoms.
FIG. 3a-3d a flow chart of a program module which performs drug selection based on the output resulting from the execution of the knowledgebase.
FIG. 4 is a block diagram showing the various hardware elements of the invented system.
DETAILED DESCRIPTION OF THE INVENTION
The invention is a system for use in pharmacies which uses customer inputs to assist the customer with the selection of an appropriate non-prescription medication. The system uses an expert system to perform the selection and thereby free-up the time of the pharmacists to the extent that customers are able to obtain information and suggestions for non-prescription medications which they would otherwise obtain from the pharmacists. In this manner, by reducing the amount of time needed by the pharmacists to answer customer questions relating to non-prescription medications, the pharmacists are able to devote more time to the filling of prescriptions and perform other tasks.
The system comprises a personal computer with a keyboard, monitor and disk drive as input/output devices with appropriate programming for prompting a user to input information which is used by a knowledgebase to determine non-prescription medications which may be purchased by the customer to relieve symptoms of injuries or illnesses covered by the knowledgebase. A suitable personal computer which may be used is an IBM 386 or compatible with a VGA color monitor and at least a 40 MByte disk drive. As shown in FIG. 1, the system incorporates six main sections or routines as follows:
1. Input Customer Information
2. Select Main Symptom
3. Execute Symptom Knowledgebase
4. Select Product Recommendation
5. Generate Session Report
6. Close Session
1. Input Customer Information
This routine prompts a user for basic customer information such as customer name, gender, and date of birth. Other items of information may also be prompted for, such as a recent blood pressure reading. If the necessary auxiliary equipment is present on the system being used, the customer may be able to have measurements such as blood pressure taken and input directly to the system. The results are then displayed for the customer as well as used internally.
Each customer selects a "password" code the first time they use a particular system. When the customer returns to the same system at another time, the customer can then identify himself or herself as an existing customer and avoid reentering the basic customer information. As a security precaution, the password code is not displayed after it is initially input. This is to help prevent anyone from misidentifying themselves as an existing customer, which would cause the wrong information to be supplied to the other knowledgebase. Suitable software for implementing the Input Customer Information routine should be apparent to a person skilled in the art. One such suitable routine in C is attached hereto as part of Appendix 1.
2. Select Main Symptom
This routine requests the customer to select one main symptom category from a list displayed. Each category corresponds to a separate knowledgebase, and the choice made results in the appropriate knowledgebase being loaded for the next routine. In the presently preferred embodiment, the list contains the following symptom categories:
a) Cough and Cold
b) Pain
c) Stomach Problems
d) Allergies
This list of symptom categories displayed to the customer is easily changed, so that new areas of selection can be added to existing systems. This allows the range of problems for which the system can supply recommendations to increase over time. Suitable software for implementing the Select Main Symptom routine should be apparent to a person skilled in the art. One such suitable routine in C is attached hereto as part of Appendix 1.
3. Execute Symptom Knowledgebase
In this routine, the knowledgebase corresponding to the main symptom category selected is loaded and executed. The logic of the knowledgebase itself determines which questions are asked of the customer during this step of the consultation. This allows new knowledgebases to be added to the system without requiring changes to the programming.
Certain inputs which may be requested by the knowledgebase, such as the customer age, are provided automatically by the system based on the information provided from responses to questions generated by the Input Customer Information routine. These questions from the knowledgebase are not seen by the user.
The output of each knowledgebase on completion is a list of component medications recommended for use with the symptoms described. The knowledgebases must also determine whether potential problems may exist with the customer using the recommended medications. In the case of such a problem, the knowledgebase continues execution to select the most appropriate medication available for the symptom within the range of medications supported. The potential customer problems, if any, are then brought to the attention of the pharmacist when the session report is generated, as described below.
The currently available knowledgebases are Cough and Cold, Pain, Stomach Problems, and Allergies. A written definition of these knowledgebases in a logic programming language form is set forth in Appendices 2-5 respectively.
A flow diagram for the execution of the Cough and Cold knowledgebase is shown in FIGS. 2a-2e. The user choices for the particular symptoms being experienced are obtained at 101. These symptoms may be one or more of Cough tested at 102, Fever at 201, General Achiness at 202, Runny Nose at 203, Sore Throat at 215, or Stuffy Nose at 302.
If the Cough symptom has been selected at 102, various tests are made to determine the need for various possible component medications. If chest congestion or phlegm is present at 104, `expectorant` is included as a component medication at 103. If chest congestion or phlegm is absent at 104, or present along with excessive coughing at 108, `antitussive` is included as a component medication at 110. If coughing in bed is being experienced at 111, `antihistamine` is included as a component medication at 114.
If the Fever symptom has been selected at 201, `antipyretic` is always included as a component medication at 204. If the General Achiness symptom has been selected at 202, `analgesic` is always included as a component medication at 205. If the Runny Nose symptom has been selected at 203, `antihistamine` is always included as a component medication at 206. If the Sore Throat symptom has been selected at 215, `oral anesthetic` is always included as a component medication at 214.
If the Stuffy Nose symptom has been selected at 302, various tests are made to select the appropriate type of component medication. If a medication has been used to treat the stuffy nose at 303, and furthermore a nasal spray has been used to treat the stuffy nose at 310, `Nasal Spray NaCl` is selected as a component medication at 311. If a medication has been used to treat the stuffy nose at 303, but not a nasal spray at 310, `decongestant topical` is selected as a component medication at 308. This same choice of `decongestant topical` at 308 is also made if no medication has been used to treat the stuffy nose at 303, but any of the following conditions is present: Heart or thyroid condition, high blood pressure, or diabetes at 305; depression, anxiety, or seizures at 306; or a male over 40 years old with difficulty in urination at 307. If no medications have been used to treat the stuffy nose at 303, and none of the above listed conditions at 305, 306, or 307 are present, `decongestant` is selected as a component medication at 309.
In this manner a list of recommended ingredients is built depending upon the symptoms and health and condition of the customer. Each type of medication, and in some cases individual types of symptoms, has conditions which indicate potential problems with the use of the medication. If such a potential problem is found with a recommended component medication, `no select` is added to the list of component medications as an indication that the pharmacist must personally review the recommendation and discuss the potential problems with the customer.
For the `expectorant` component medication, any of the following conditions will result in `no select` being included as a component medication at 109: Asthma, emphysema, pulmonary disease, or shortness of breath at 105; smoker at 106; or coughing up excess phlegm at 107.
For the Cough symptom in general, `no select` is included at 115 if either the cough has lasted more than 6 days at 112, or chest pain is present at 113. For the Fever symptom, `no select` is included at 213 if either the fever has lasted more than 3 days at 207 or the fever level is greater than 100 degrees at 210. For the General Achiness symptom, `no select` is included at 211 if the achiness has lasted more than 6 days at 208. For the Runny Nose symptom, `no select` is included at 212 if the runny nose has lasted more than 6 days at 209. For the Sore Throat symptom, `no select` is included at 217 if the soreness has lasted more than 2 days at 216. For the Stuffy Nose symptom, `no select` is included at 304 if the stuffy nose has lasted more than 6 days at 301.
For the `antitussive` component medication, any of the following conditions will result in `no select` being included as a component medication at 411: Asthma, emphysema, pulmonary disease, or shortness of breath at 404; smoker at 406; or a male over 40 years old with difficulty in urination at 408. For the `antihistamine` component medication, any of the following conditions will result in `no select` being included at 412: over 8 years old at 403; asthma, emphysema, pulmonary disease, or shortness of breath at 405; glaucoma at 407; a male over 40 years old with difficulty in urination at 410; or depression, anxiety, or seizures at 409.
Certain other conditions always result in `no select` being included as a component medication regardless of the particular symptoms selected or component medications recommended. A `no select` is included at 506 if the recommendation is for a female at 501 more than 12 years old at 502 who is either: pregnant or a nursing mother at 503; or less than 55 years old at 504 and taking a prescription medication other than birth control pills at 507. A `no select` is included at 508 if the recommendation is for anyone taking a prescription medication at 505 who is not female at 501, or not more than 12 years old at 502, or more than 55 years old at 504.
The execution of the other knowledgebases is similar in that the customer's symptoms and general health are evaluated and a list of ingredients is added to a recommended ingredients list depending upon the customer's symptoms and health with a no-select condition indicated in the event that over the counter medications are not suitable based upon the customer's symptoms, general health or condition.
4. Select Product Recommendation
This routine takes the list of component medications generated by the execution of the knowledgebase and searches a database to find the appropriate product to be recommended. The products are classified by component medications, with the products to recommend within each classification selectable by pharmacy or management personnel without change to the system. Separate recommendations are recorded for different age groups as well.
The database files also control whether multiple-ingredient products can be recommended. If multiple-ingredient products are allowed, which is a function of the philosophy of the pharmacy or pharmacist, the system attempts to find a classification which matches as many of the recommended component medications as possible without including any component medications which are not included in the recommended list.
Therapeutic Class Numbers are used within the database files to identify the component medications present in a product. Each particular combination of component medications used, including the individual component medication as a single-ingredient product, is assigned a unique Therapeutic Class Number. Products present in the database files are classified by their associated Therapeutic Class Numbers, so that all products having some particular combination of component medications can be easily found by using the appropriate Therapeutic Class Number.
Each Therapeutic Class Number may have an associated qualifier code, which is used to indicate a subtype of a component medication. This allows the program to distinguish between medications which are functionally equivalent but differ in their usage criteria
When multiple-product choices are available within a classification, the customer is asked to pick between the choices based on the different characteristics of the products. For example, if one possible product recommendation contains sugar and another does not, the customer will be asked if they prefer a medication containing sugar.
After selecting the first product to be recommended, the component medications present in this product are removed from the list of recommended component medications. If any component medications remain in the resulting list, another product is selected in the same way. This continues until each component medication recommended by the knowledgebase is present in one and only one recommended product.
A flowchart which may be used to implement the Select Product Recommendation routine is shown in FIGS. 3a-3d. First, if the recommended component medications list referred to herein as the recommended ingredients list generated by the execution of the knowledgebase includes `antipyretic`, it is replaced by `analgesic` at 601, since the two types of ingredients are interchangeable for the range of products supported. If any duplications are present on the recommended ingredients list they are also eliminated at this point. A list of Therapeutic Class Numbers is then initialized by indicating that each has not yet been tried for product selection at 604.
A main program loop is then entered, which at the top level begins at 606. This loop is executed repeatedly until the recommended ingredients list is empty at 606. The first step in this loop is to select a Therapeutic Class Number to be used. This is done by a function call at 608, with details shown in FIGS. 3b and 3c and described below.
If the function call fails to find a usable Therapeutic Class Number at 609, an error indication is set to show that a recommended ingredient was not found at 612 and the first recommended ingredient is eliminated from the list at 615 before returning to the beginning of the main program loop. If the function call succeeds at 609, an indication is set that the Therapeutic Class Number selected has been tried at 602. A list of possible product selections with that Therapeutic Class Number is then generated. This is done by a second function call at 603, with details shown in of FIG. 3c and described below.
If the function call fails to find any usable products with the selected Therapeutic Class Number at 605, execution returns to the beginning of the main program loop. Otherwise, a secondary selection loop is entered that continues until only one product is left in the drug selection list at 607. If more than one product is present in the list, the first characteristic by which products in the list differ is found at 610 and the customer is asked to choose based on that characteristic at 611. For example, if the medication is available in both tablet and liquid form, the customer is asked which form is preferred. All products which do not match the customer preference are then eliminated from the list at 614 before returning to the start of the secondary selection loop.
Once the drug selection list has been reduced to a single choice at 607, the product remaining on the list is added to the recommended drug list at 613 and all component ingredients present in the product are eliminated from the recommended ingredients list at 616. Execution then returns to the start of the main program loop.
The Select Therapeutic Class Number function flow is shown in FIGS. 3b and 3c. This function first checks whether multiple ingredient drugs recommendations are allowed at 701, as determined by the pharmacist when setting up the system. If so, a target match count value is set to the total number of component medications in the recommended ingredients list at 702. This will cause the Therapeutic Class Number selection to include as many of these ingredients as possible. If multiple ingredient drug recommendations are not allowed at 701, the target match count value is set to 1 at 703 so that only the first component medication on the recommended ingredients list will be considered when selecting a Therapeutic Class Number.
Next a check is made for the case where the only recommended ingredient being considered is `decongestant` at 704. If this case applies, the user is asked to choose between an oral and a topical decongestant, and the choice made is substituted for `decongestant` in the recommended ingredients list at 705.
After this, the best match count found is set to 0 and the selected Therapeutic Class Number is set to `none` at 706.
A loop is then entered to find the Therapeutic Class Number to be used. The first step in this loop sets the current position in the Therapeutic Class Number list to the start of the list 801. Within this main loop, an inner loop is then entered which continues until the end of the Therapeutic Class Number list is reached at 802.
The first step in this inner loop is to find the number of component ingredients for the current Therapeutic Class Number 803. If this count is greater than the best match count found previously, and less than or equal to the target match count 805, and each component ingredient for the current Therapeutic Class Number is one of the recommended ingredients being considered 807, and either there is no qualifier present for the current Therapeutic Class Number or the qualifier has not been checked previously 809, the selected Therapeutic Class Number is set to the current one in the list and the best match count found is set to the number of component ingredients 811. Whether these conditions succeed or fail, the current position in the Therapeutic Class Number list is advanced to the next in the list 812, and execution continues at the beginning of the inner loop.
When the end of the Therapeutic Class Number list is reached 802, the selected Therapeutic Class Number is checked before being returned to the caller. If a Therapeutic Class Number was selected at 804, and a qualifier code is present for the Therapeutic Class Number 806, the appropriate knowledgebase is invoked to check whether the qualifier code may be used 808. If no Therapeutic Class Number was selected 804, or no qualifier code is present for that Therapeutic Class Number 806, the result is returned directly.
A knowledgebase invoked to check the usability of a qualifier code may request any necessary information from the user in order to determine whether the qualifier is allowed. The only knowledgebase currently defined for checking qualifier codes is the MOD99 knowledgebase which is defined in Appendix 6. This knowledgebase checks the usability of various types of analgesics.
If the result of the knowledgebase invocation is to reject the qualifier specified for the selected Therapeutic class number 810, the main loop is restarted 801 to select another Therapeutic Class Number. If the qualifier is accepted 810, it is returned to the caller.
The Generate Drug Selection List function flow is shown in FIG. 3d. This function first initializes the drug selection list to empty and sets the current position in the drug database to the start at 901. It then begins a loop to generate the drug selection list. The first step in the loop is to search the drug database for the next drug with the selected Therapeutic Class Number at 902. If a drug is found at 903, it is then checked to determine if the pharmacist has selected this product for recommendation to the age range that includes this customer at 904. If the drug has been selected for recommendation, it is then added to the drug selection list at 905. Whether selected or not, execution then returns to the start of the loop. When no more drugs with the selected Therapeutic Class Number are found at 903, the generated drug selection list is returned to the caller.
Suitable software for implementing the Select Product Recommendation routine should be apparent to a person skilled in the art. One such suitable routine in C is attached hereto as Appendix 7.
5. Generate Session Report
The next routine generates a session report for the customer, which may be printed immediately or queued for later printing. This report includes a summary of the customer information provided to the system, along with a detailed list of the questions which have been asked by the system and the responses the customer made. If the knowledgebase found any potential problems with the customer using the recommended medications during the execution of the symptom knowledgebase, the report is prefaced with a header page to alert the pharmacist that a problem may exist. The relevant portions of the session summary are then printed differently to draw them to the pharmacist's attention.
The actual product recommendations follow the session summary. For each recommended product, the system prints the product name and a summary of usage information for the product. This information may include warnings and usage restrictions as well as actual directions for use. Other information, such as location in the store and price, may also be included. Coupons for purchasing the product at a discount may also be printed with the recommendation information.
Suitable software for implementing the Generate Session Report routine should be apparent to a person skilled in the art. One such suitable routine in C is attached hereto as Appendix 8.
6. Close Session
This routine asks the customer if they have another symptom for which they wish to consult the system. If the answer is "yes", the program returns to the Select Main Symptom step to select the new main symptom category. If the answer is "no" the customer is thanked for using the system and referred to the pharmacist to obtain the printed report.
Suitable software for implementing the Close Session routine should be apparent to a person skilled in the art. One such suitable routine in C is attached hereto as part of Appendix 1.
Various "#include" files used to generate the programs are provided in Appendix 9 as DATA.H, DEFS.H, SCREEN.H, VARS.H, and VERSION.H.
FIG. 4 is a block diagram showing suitable hardware which may be utilized to implement the invented system. The system includes a personal computer 911 having a keyboard 913 for use data input, a monitor 915 to display the prompts and provide feedback to the user for data which is input, disk drive 921 on which are stored the various knowledge bases such as the cough and cold knowledgebase illustrated in FIG. 2a. database 931 utilized by the Select Product Recommendation routine and system routines 935 which are the various program modules labeled 1-6 in FIG. 1 as described above. Also shown in FIG. 4 is printer 941 onto which the session report generated by the Generate Session Report module may be printed. The various hardware elements 911, 913, 915, 921 and 941 are readily available components, the specifics of which are not important to an understanding of the invention. The knowledgebase 925, database 931 and system routines 935 contain information as described herein which is loaded into the memory of personal computer 911 for execution and to provide data used by the routines executed by personal computer 911. ##SPC1##
Claims
We claim:
1. A system including a personal computer having an input device, a display, a storage device and a processor adapted to execute a computer program loaded from said storage device into a random access memory, said system for assisting a user to select appropriate non-prescription medications, said system comprising: a) means for prompting the user to input identifying information to uniquely identify the user from the other uses of the system and to input predetermined information for subsequent use by execution by said processor of said computer program causing first prompting information to be displayed on said display; b) said input device for allowing the user to input said identifying information to uniquely identify the user from other uses of the system, to answer predetermined questions and to input said predetermined information, c) means for prompting the user to select a main symptom of an illness or injury by execution of said computer program causing second prompting information to be displayed on said display, said input device for allowing the user to select said main symptom; d) means to generate a list of ingredients of non-prescription medications, wherein said list generation means is a knowledgebase loaded from said storage device in to said random access memory which when executed by said processor, generates predetermined questions which are displayed on said display based upon the inputted identifying information, the inputted predetermined information and the selected main symptom, and uses the user's answers to the predetermined questions to generate said list of ingredients, and wherein said knowledge base determines the existence of potential problems with the customer using non-prescription medications which contain at least one ingredient on said list of ingredients; e) means using the generated list of ingredients and any determined potential problems to generate a report of recommended non-prescription medications which may be purchased to relieve the symptoms of the selected illness or injury, said generated respect being generated by execution by said processor of said computer program which causes said generated report to appear on said display.
2. The system defined by claim 1 wherein said report generating means uses said generated list of ingredients to search a database containing products with their component medications, and after selecting a first product containing as a component medication at least one ingredient from said generated list of ingredients, removes the component medication present in the selected product from the generated list of ingredients, and if any items remain in the resulting list, selects a second product containing as a component medication at least one ingredient from said resulting list, and then continues said selection and removal from said resulting list until each component medication in the generated list of ingredients is present in one and only one selected product.
3. A method for assisting a user to select appropriate non-prescription medications using a personal computer having an input device, a display, a storage device and a processor adapted to execute a computer program loaded from said storage device into a random access memory, said method comprising the steps of: a) prompting the user on said display to input the identifying information to uniquely identify the user from other users of the system and to input predetermined information for subsequent use; b) inputting with said input device said identifying information and said predetermined information supplied by the user; c) prompting the user on said display to select a main symptom of an illness or injury; d) inputting with said input device said main symptom selected by the user; e) generating list a list of ingredients of non-prescription medications, wherein said list of ingredients is generated by the execution of a knowledgebase loaded from said storage device into said random access memory which generates predetermined questions based upon the inputted identifying information, the inputted predetermined information and the selected main symptom, and uses the user's answers to the predetermined questions input with said input device to generate said list of ingredients, and wherein said knowledge base determines the existence of potential problems with the customer using non-prescription medications which contain at least one ingredient on said list of ingredients; f) using the generated list of ingredients and any determined potential problems to generate a report of recommended non-prescription medications which may be purchased to relieve the symptoms of the selected illness of injury.
4. The method defined by claim 3 wherein said report generation step uses said generated list of ingredients to search a database containing products with their component medications, and after selecting a first product containing as a component medication at least one ingredient from said generated list of ingredients, removes the component medication present in the selected product from the generated list of ingredients, and if any items remain in the resulting list, selects a second product containing as a component medication at least one ingredient from said resulting list, and then continues said selection and removal from said resulting list until each component medication in the generated list of ingredients is present in one and only one selected product.
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