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Guide - Prescribing a Drug

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Professional Practice Standard

Published: August 2018

Revised: October 2018, March 2019, June 2022

Introduction 

Under the Veterinarians Act and regulations, a veterinarian licensed by the College of Veterinarians of Ontario is authorized to prescribe and dispense drugs. More specifically, prescribing drugs is an important component of the practice of most veterinarians and one that requires appropriate knowledge and skill, and the use of professional judgment. Prescribing is most often coupled with the act of administering and/or dispensing. There are instances when a veterinarian will only perform the act of prescribing. A veterinarian should acknowledge and manage the potential conflict of interest in assuming the dual role of prescriber and dispenser.  

Using a question-and-answer format, this Guide to the Professional Practice Standard: Prescribing a Drug addresses questions and offers suggestions on how to apply the Professional Practice Standard in situations that arise in veterinary practice. 

General Expectations
No, a veterinarian may not delegate the act of prescribing to an auxiliary. 

When determining which drug to prescribe, a veterinarian uses their clinical judgment to recommend the most appropriate course of treatment for an animal(s) or group of animals, taking into consideration the following: 

  • The availability of any approved veterinary drugs for the species in question and condition (on-label use);  
  • The availability of veterinary drugs or approved human drugs (extra-label use);  
  • The need for a compounded drug where no approved drug exists, and a therapeutic need is established;  
  • Current research and evidence of available treatments; and  
  • Considerations such as side effects, risks, and benefits. 

A veterinarian uses professional judgement to provide their recommendation of treatment options on a case-by-case basis taking into consideration factors such as the risks and benefits of each, and the circumstances of the patient and client. The veterinarian obtains informed client consent in accordance with the Professional Practice Standard: Informed Client Consent.

Every veterinarian has a valuable role to play in the effort to combat antimicrobial resistance and to preserve the effectiveness of antimicrobial drugs and their availability for both veterinary and human use. As part of good stewardship, the College expects a veterinarian will assume an active leadership role by ensuring their understanding of: 

  • the need for antimicrobial oversight;  
  • the existing government directives;  
  • the evolving science related to pharmaceuticals (continued on next page);  
  • sustaining the clinical efficacy of the drug by optimizing drug use, choice, dosing, duration, and route of administration while minimizing the emergence of resistance and other adverse effects; and  
  • the most appropriate current use of antimicrobial drugs with a specific species. 

A veterinarian must only prescribe antimicrobial drugs within a veterinarian-client-patient relationship (VCPR) and where strong clinical evidence demonstrates medical need. A veterinarian must also maintain a medical record that contains sufficient information to support the prescription and use of an antimicrobial drug. For more information on medical recordkeeping, see the Professional Practice Standard: Medical Records. It is important for veterinarians to be vigilant in their oversight and to remain ever cognizant that there are risks as well as benefits associated with antimicrobial use for the greater public good. 

A veterinarian may establish standard operating protocols (SOPs) for an animal(s) or group of animals in advance or anticipation of illness, vaccination, processing, etc. An SOP is a specific direction or series of steps to be undertaken following a specific scenario or indication. An SOP is not a prescription and does not authorize the dispensing of a drug. 
Adverse Reactions 
As a part of the informed consent discussion with a client, a veterinarian should discuss the risks associated with a prescribed drug. This should include a discussion of the common side effects, any serious risks associated with the administration of a drug, proper storage and handling, and the means of administration. This information can also be provided in a handout. A notation that the information was provided should be made in the medical record in accordance with the Professional Practice Standard: Medical Records. 
A veterinarian prescribing a drug must be readily available in-person during both regular-hours and after-hours in case of adverse reactions to the drug or failure of the regimen of therapy. Adverse reactions to a drug that occur after-hours may be handled directly by the prescribing veterinarian or through an arrangement with another veterinarian/veterinary facility.  

For more information on being readily available in-person to treat adverse reactions during after-hours, see the Policy Statement: After-Hours Care Services. 

A veterinarian is encouraged to report suspected adverse drug reactions that occur in their practice to the Veterinary Drugs Directorate (VDD). The Veterinary Drugs Directorate classifies an adverse reaction to a veterinary drug as: 

  • Any unintended or noxious side effects, injury toxicity or sensitivity reaction associated with the clinical uses, studies, investigations and tests respecting a drug; 
  • any unusual failure of a drug to produce its expected pharmacological activity. 

The VDD suggests that the following kinds of adverse drug reactions be reported: 

  • All suspected drug adverse reactions which are unexpected: an undesirable patient effect which is not consistent with product information or labelling; 
  • all suspected drug adverse reactions which are serious: an undesirable patient effect which contributes to significant disability or illness, which requires hospitalization or significant medical intervention, or which is more severe or more frequent than expected from product information or labelling; 
  • all suspected drug adverse reactions to recently marketed drugs (commercially available for less than 7 years), regardless of nature or severity; and 
  • lack of efficacy when the drug was used according to product labelling (species, dose, indications, route of administration). 

Details on how to report can be found here: https://www.canada.ca/en/healthcanada/services/drugs-health-products/veterinary-drugs/adverse-drug-reactions-adrs.html#a6  

Canada is part of a global food animal residue avoidance databank program known as the Canadian Global Food Animal Residue Avoidance Database (CgFARAD). Based at the Western College of  Veterinary Medicine in Saskatoon, Saskatchewan and the Ontario Veterinary College in Guelph, Ontario, the CgFARAD provides information on residue avoidance to Canadian veterinarians.  

A veterinarian should consult CgFARAD ( www.cgfarad.usask.ca ) for residue avoidance information when prescribing a drug with a Health Canada Drug Identification Number (DIN) in an extra-label manner. 

A veterinarian must advise the client of appropriate withholding times when prescribing a drug for use in a food-producing animals. The appropriate withholding times must be documented in the medical record, on written prescriptions, and on the dispensing label. CgFARAD  (www.cgfarad.usask.ca ) should be consulted for recommended residue avoidance information when prescribing a drug with a Health Canada Drug Identification Number (DIN) in an extra-label manner. For more information on withholding time requirements, see the Professional Practice Standard: Prescribing a Drug. 
Conflicts of Interest and Prescribing 

The potential for a conflict of interest in veterinary medicine may arise because a veterinarian is in a position to derive financial benefit from dispensing the medications that they prescribe, which has the potential to influence the motivation or decision-making of that veterinarian that may not be in the best interest of the patient or client.  

A veterinarian should be alert to the potential for conflict of interest, and should ensure that the process of prescribing drugs is transparent, is performed on the basis of medical need, and that the client’s choice to have a prescription filled wherever they choose is respected. 

 For further information on Conflict of Interest, see the Professional Practice Standard: Conflicts of Interest in the Practice of Veterinary Medicine. 

Prescribing via Telemedicine
A veterinarian is permitted to prescribe a drug for an animal(s) or group of animals via telemedicine. The professional expectations related to this allowance are outlined in the Professional Practice Standard: Prescribing a Drug and are repeated in the Professional Practice Standard: Telemedicine. 
There are specific circumstances where a veterinarian is permitted to prescribe a non-controlled drug to an animal(s) or group of animals for an immediate, short-term need when they have obtained recent and sufficient knowledge through a virtual physical examination or virtual premise visit. The professional expectations related to this allowance are outlined in the Professional Practice Standard: Prescribing a Drug and are repeated in the Professional Practice Standard: Telemedicine. 

A veterinarian could consider the following options in this scenario: 

  • Using telemedicine, establish a veterinarian-client-patient relationship (VCPR) and obtain recent and sufficient knowledge through a virtual physical examination or virtual premise visit in order to prescribe a non-controlled drug for an immediate, short-term need. The professional expectations related to this allowance are outlined in the Professional Practice Standard: Prescribing a Drug and are repeated in the Professional Practice Standard: Telemedicine. 
  • Conduct an in-person premise visit to establish a veterinarian-client-patient relationship (VCPR) and obtain recent and sufficient knowledge required to prescribe any drug. For companion animal practice, the College's Council has taken the position that it is in the public interest for a veterinarian who is working from an accredited facility, but who does not have an accredited companion animal mobile facility, to be able to attend on rare occasions at the animal(s)' location when an in-person premise visit is in the best interest of the client and/or animal(s). For more information on this allowance, please refer to the Accreditation section of the College’s website. 

A veterinarian who prescribes a drug must be readily available in-person during both regular hours and after-hours in case of adverse reactions to the drug or failure of the regimen of therapy. Adverse reactions to a drug that occur after-hours may be handled directly by the prescribing veterinarian or through an arrangement with another veterinarian/veterinary facility.  

For more information on being readily available in-person to treat adverse reactions during after-hours, see the Policy Statement: After-Hours Care Services. 

The quantity of the non-controlled drug prescribed is limited to an immediate, short-term need or is the minimum amount necessary to allow the client a reasonable opportunity to obtain in-person veterinary services for the animal(s) or group of animals. It is the veterinarian’s professional judgement to prescribe the appropriate amount based on the specific circumstances presented. 

A veterinarian is permitted to prescribe any drug via telemedicine within an existing VPCR when they have first obtained recent and sufficient information through an in-person physical examination or in-person premise visit. This includes controlled drugs.  

Veterinarians are reminded that controlled drugs are only to be prescribed when: 

  1. The animal for which the controlled substance is prescribed or dispensed or to which it is  
  2. administered is an animal under their professional treatment; and 
  3. The controlled substance is required for a condition for which the animal is receiving treatment from the member.

A veterinarian is not permitted to prescribe a controlled drug via telemedicine for new clients unless they have first obtained recent and sufficient knowledge from an in-person physical examination or in-person premise visit.

A veterinarian is also not permitted to prescribe a controlled drug via telemedicine within an existing VCPR if the animal(s) or group of animals is presented with a new condition that the veterinarian does not have recent and sufficient knowledge of from an in-person physical examination or in-person premise visit. A veterinarian is permitted to use their professional judgement to determine whether they possess the required information within these parameters. 

Prescriptions 
Once a veterinarian has determined that a drug is warranted for a patient, a client can choose to have the medication dispensed from the veterinary facility or request that a written prescription be provided to be filled at a pharmacy of the client’s choice. If a client requests a written prescription, a veterinarian is obligated to provide it as per Regulation 1093 section 26. 

A veterinarian has several options when prescribing a drug either in-person or via telemedicine. They can inform the client that: 

  1. A drug may be dispensed from the veterinarian’s accredited facility;  
  2. A prescription may be written for the client to take to a pharmacy of their choosing;  
  3. An oral prescription may be provided to a veterinarian licensed by the College of Veterinarians of Ontario, a member of the Ontario College of Pharmacists or a veterinarian practising outside of Ontario; or  
  4. The prescribed drug can be mailed (registered) or couriered to the client in accordance with Regulation 1093, Section 33. 

When an oral prescription is provided to a veterinarian licensed by the College of Veterinarians of Ontario for dispensing the drug, that veterinarian must determine if it is appropriate to do so in accordance with the Professional Practice Standard: Dispensing a Drug. For more information on prescribing and dispensing in these circumstances see the Professional Practice Standard: Prescribing a Drug and the Professional Practice Standard: Dispensing a Drug. 

The following information pertains to drugs that are available in Canada and have been approved by Health Canada:  

Once the client is provided with a prescription, it is left to them to decide where they will have the prescription filled. The determination of the validity of a veterinary prescription is made by the dispenser. In some cases, some pharmacies will accept prescriptions from veterinarians not licensed in the jurisdiction in which the pharmacy is located, some will not. The integrity of the drug is the responsibility of the dispensing pharmacy, and they are required to follow the pharmacy regulations in their jurisdiction.  

For oral or faxed prescriptions, a veterinarian can only deal directly with a pharmacist licensed in Ontario, another member of the College of Veterinarians of Ontario, or a licensed veterinarian practising outside of Ontario.  

In addition, a veterinarian may wish to educate their client about the risks associated with purchasing drugs online, as outlined by Health Canada: Buying drugs over the internet - Canada.ca. The College regulates the practice of veterinary medicine in Ontario, including the issuance of prescriptions and the dispensing of drugs, but the regulation of pharmacies – in Ontario or elsewhere – is not within the jurisdiction of the College or its licensed veterinarians. 

If a veterinarian is treating animals of the same species (including companion animals) as a group within an established VCPR it is acceptable to provide one prescription or dispensed product with directions for treating the group. It is also acceptable to provide one prescription that can be used to treat multiple animals over an extended period of time, and at different times, for the same disease as long as it is within the confines of the VCPR. However, this does not apply to controlled drugs which may only be prescribed to individual animals.

Scenario: 

A veterinarian has an established veterinarian-client-patient relationship (VCPR) with the local humane  society to provide veterinary services to the animals under their care. Two cats from the humane society are assessed by the veterinarian and diagnosed with a highly contagious skin disease. The veterinarian is informed that more cats at the humane society may be affected, and they are concerned about further spread. Given their knowledge of the population of cats and previous on-site visits, the veterinarian prescribes and dispenses medication with directions for treating the group of cats currently affected and establishes a standard operating protocol (SOP) to be followed should other cats start showing clinical signs of the disease. 

Yes, a veterinarian may choose to charge a fee for providing this service. 

A veterinarian may choose to write multiple drugs on a single prescription or to separate each out individually. In cases of varying start times, it is recommended that separate prescriptions be written for each drug prescribed. 

A veterinarian is permitted to electronically sign a prescription only if they have ensured that they are using an electronic computer system that has a secure method that permits only the member to apply an electronic signature. 
Controlled Drugs 
A veterinarian should be aware of how to recognize behaviours that can indicate drug-seeking and how to prevent abuse and diversion of controlled drugs. A veterinarian can choose to prescribe a non-controlled drug for their patient instead where appropriate. A veterinarian should ensure that all requests for prescriptions are documented in the medical record in accordance with the Professional Practice Standard: Medical Records. 
Refills
When writing a prescription, a veterinarian must write down the number of refills that are permitted, if any are to be provided, the expiry date of the prescription itself, or the total amount of the drug that is being prescribed. In all cases, the amount and duration of a prescription must be determined while ensuring that the veterinarian has and maintains recent and sufficient knowledge of the animal(s) or group of animals. 

Prescribing with refills is often appropriate for patients with chronic conditions that are likely to remain stable for the duration of the dispensing period. A veterinarian should ensure processes are in place to monitor the ongoing appropriateness of the drug when prescribing with refills. This includes maintaining recent and sufficient knowledge of the patient and condition by conducting periodic re assessments looking for any changes in the underlying chronic condition, as well as any new drug interactions or contraindications, and/or new side effects of the prescribed drug.  

When a client requests that a veterinarian authorize a refill on a prescription that has run out, they must consider whether the drug is still appropriate, and whether the patient’s condition is stable enough to warrant the prescription refill without further assessment. If a veterinarian is concerned that continuing to dispense medication without examining and/or performing diagnostic tests on their patient could result in risk to the patient’s health, this should be reviewed with the client as part of the client education and informed consent discussions. The veterinarian is to use their professional judgement to decide when to dispense a medication, the dosage, and the frequency.  

It is recommended that a veterinarian also consider whether a request for a prescription refill received earlier or later than expected may indicate poor adherence, possibly leading to inadequate therapy or an adverse event. 

A veterinarian must determine if the refill is warranted for the patient first and if any further assessment of the patient is required before issuing the prescription. This will likely require a discussion with the client. Once it is determined that a refill should be issued, it is suggested that a veterinarian write a prescription to give to a client, rather than fill out a prescription request form from a pharmacy (which may be outside of Ontario). 
Legislative Authority

Food and Drugs Act and Regulations (Federal)  
Feeds Act and Regulations (Federal)  
Controlled Drugs and Substances Act and Regulations (Federal)  
Drug and Pharmacies Regulation Act and Regulations (Provincial)  
Drug Interchangeability and Dispensing Fee Act (Provincial)  
Veterinarians Act (Provincial)  
Regulation 1093, s. 1, 18, 23-33 (Veterinarians Act) (Provincial) 


Resources

The following can be found at the College‚Äôs website at cvo.org 

  1. Professional Practice Standard: Prescribing a Drug 

  1. Professional Practice Standard: Dispensing a Drug 

  1. Guide to the Professional Practice Standard: Dispensing a Drug 

  1. Professional Practice Standard: Extra-Label Drug Use 

  1. Guide to the Professional Practice Standard: Extra-Label Drug Use 

  1. Professional Practice Standard: Management and Disposal of Controlled Drugs 

  1. Guide to the Professional Practice Standard: Management and Disposal of Controlled Drugs 

  1. Professional Practice Standard: Use of Compounded Drugs in Veterinary Practice 

  1. Guide to the Professional Practice Standard: Use of Compounded Drugs in Veterinary Practice 

  1. Professional Practice Standard: Informed Client Consent 

  1. Guide to the Professional Practice Standard: Informed Client Consent 

  1. Professional Practice Standard: Medical Records 

  1. Guide to the Professional Practice Standard: Medical Records 

  1. Professional Practice Standard: Establishing, Maintaining and Discontinuing a Veterinarian-Client-Patient Relationship (VCPR) 

  1. Guide to the Professional Practice Standard: Establishing, Maintaining and Discontinuing  a Veterinarian-Client-Patient Relationship (VCPR) 

  1. Policy Statement: After-Hours Care Services 

  1. Professional Practice Standard: Conflicts of Interest in the Practice of Veterinary Medicine 

  1. Professional Practice Standard: Telemedicine 

  1. Policy on Extra-Label Drug Use in Food Producing Animals, Health Canada, 2015. http://www.hc-sc.gc.ca/dhp-mps/vet/label-etiquet/pol_eldu-umdde-eng.php  

  1. Canadian gFARAD Website: https://cgfarad.usask.ca/index.php  

College publications contain practice parameters and standards which should be considered by all Ontario veterinarians in the care of their patients and in the practice of the profession. College publications are developed in consultation with the profession and describe current professional expectations. It is important to note that these College publications may be used by the College or other bodies in determining whether appropriate standards of practice and professional responsibilities have been maintained. The College encourages you to refer to the website (www.cvo.org) to ensure you are referring to the most recent version of any document.