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Drugs in Dental Hygiene Practice Examination

Registered Dental Hygienists who want to include prescribing, dispensing or selling Chlorhexidine (the only prescription drug listed in the Designated Drugs Regulation) in their practice must successfully complete the Drugs in Dental Hygiene Practice Examination (DDHPE).

The exam is open book and includes 75 multiple-choice questions around five domains. You must correctly answer 60 questions to be successful and there is no limit on the number of times you can attempt the exam. The exam takes two hours to complete and it is timed. There is no fee to take the DDHPE.

Preparing for the DDHPE

To upgrade your pharmacology knowledge beyond the refresher course before taking the DDHPE and/or self-study component, see the dental hygiene pharmacology courses available through OntarioLearn.

Time to prepare can vary depending on your pharmacology knowledge, but it is around 25 hours. You can use these hours in your learning portfolio to demonstrate compliance with your continuous competency requirement.

Frequently Asked Questions

What happens if I have technical difficulties during the exam?

The examination is hosted and delivered by an outside company that has years of experience with electronic examinations. Address any technical difficulties to

What if I require an accommodation?

CDHO will make every effort to accommodate registrants unable to complete the examination as designed due to documented special needs.

I moved from Alberta and was able to prescribe there. Do I still need to take the examination?

Yes. All Ontario registrants must complete the DDHPE before prescribing, dispensing or selling drugs in Ontario.

Examination Ethics

In taking the examination you cannot:

  • Log in to the system and complete the final quiz for any other Registered Dental Hygienist or have any other person log in to complete the module for you.
  • Copy, photograph or attempt to replicate the examination questions.
  • Distribute the examination questions or responses to other persons.
  • Seek answers to the examination questions from the College.

Breaching these principles may result in being referred to the Inquiries, Complaints and Reports Committee (ICRC). That could lead to a referral to the Discipline Committee.