Dosing – Understanding your prescription
Looking at your prescription as you leave a doctor’s office can cause confusion. Many medications have specific doses and frequency associated with them. These doses and frequency are not only specific to the medication but also to the patient and the condition.
Health Canada requires manufacturers of medicines to do extensive research to determine the appropriate dose for the condition the medicine is designed to treat. This research (also referred to as Phase II and Phase III research) looks to determine the safest to dose of medicine to ensure the maximal efficacy with the least side effects or adverse events in the patient population the medicine is targeted. (eg. children, elderly)
Most doses are expressed in milligrams (MG) per unit. For example, 10 mg capsule, will have 10mg of active drug. The capsule will have other substances in there including preservatives, and other non medicinal ingredients that help preserve the integrity of the medication until its expiry date. All ingredients must be approved by Health Canada.
The actual dosage of each drug in mg doesn’t mean to indicate its strength when it’s compared to another drug. For example, a 10 mg dose of one medicine may actually have a stronger effect in the body than another medicine that has an 80mg strength for the same condition.
Your health care professional is knowledgeable on the approved doses for each medicine. They are required prescribe and dispense the right drug at the right dose for the right patient.
Frequency of Doses
Our body has mechanisms to help get rid of medications as it does other substances such as digesting food, or drinks. In order for a medication to be safe and as effective we need to maintain a certain concentration or level in the body throughout therapy. To achieve this, some medications may have to be given more than once a day. Giving one high dose of certain medication can increase side effects and can wear off in the body by the end of the day providing lack of efficacy. This is why some medications have to be administered more than once a day rather than once daily. Manufactures work with health care professional to help create new release mechanisms and formulation to help make it easier to take medications. New formulations can make medications be taken once daily, once weekly or even annually while maintaining efficacy and safety.
Every patient is different in their reaction to medicines. Factors that can contribute to that reaction are age, sex, any organ dysfunction (liver, Kidneys), other medications and even diet. If not taken into account, these factors can cause some serious side effects or can cause the medication not to work as intended. It is the responsibly of health care professionals to ensure that these factors are taken into account when a medication is prescribed or dispensed.
Talk to your Health Care Professional
Your Pharmacist is a great resource to help you understand how medications work. Many medications work in similar ways but may inappropriate for patients’ due to frequency of dosing, or patient factors as mentioned here. Your Health Plan’s medication formulary takes into account these factors and ensures that there are enough options to meet client needs.
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This article was provided by the clinical pharmacy at Rx Infinity. Rx Infinity provides optimal and sustainable patient management solutions through customized programs, innovative technology and added value services that improve the overall patient experience; while helping payers and plan sponsors achieve sustainability in the management of drug plans expenditures.
This information is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions about your medical condition. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here.