All topics

Medications and side effects

Published on May 10, 2024 at 8:00 / Updated on May 25, 2024 at 8:00

When we consider taking a medication, we typically think about the desired effects that will relieve the discomfort we're experiencing (illness, symptoms, etc.). These are known as the therapeutic or desired effects of the medication.

However, a medication can also cause additional effects, which are known as side effects. When a side effect is unpleasant or causes discomfort, it's called an adverse effect or reaction.

Causes and triggers

An adverse reaction can have different origins. Examples include:

  • An allergic reaction or intolerance
  • How the medication works (e.g., an antibiotic that kills both bad and good bacteria)
  • An interaction between multiple drugs, whether obtained over the counter or by prescription
  • Inadequate dosage (e.g., a dose that's too high or not taken at the right time)

Adverse effects can vary from one medication to another, but also from person to person (depending on health status, age, and sex). They can also differ in the following ways:

  • They can appear immediately, after a few days, or even after several months
  • Some are very obvious, while others may go unnoticed or even require extensive testing to detect
  • They can persist throughout the course of treatment or be only temporary
  • They can cause complications if left untreated in some cases


Some adverse effects are only temporary and disappear over the course of treatment. However, if a particular adverse effect persists, it's often possible to avoid it by taking the following measures:

  • Taking the medication as indicated
  • Changing your diet or lifestyle
  • Adjusting your dosage, the duration of treatment, or when you take the medication.

When should I see a health care professional?

Consult your health care provider if you experience symptoms you think may be caused by a medication. This is especially important if your symptoms are severe or have persisted for several days.

The following table presents some of the adverse effects that can be mitigated or reduced by adopting a few simple measures. Consult your pharmacist before trying them.

Adverse effectWhat you can do
Heartburn Take your medication with food.
Constipation Drink plenty of fluids.
Exercise regularly.
Increase your fibre intake.
ItchingApply wet compresses.
Diarrhea Drink plenty of fluids to prevent dehydration.
Dizziness Avoid sudden movements and rapid changes in position.
Avoid activities that require concentration, such as driving and precision work.
Take your medication in the evening.
Insomnia (difficulty sleeping) Take the medication earlier in the day.
Use relaxation techniques at bedtime.
Sun sensitivity Limit your sun exposure and avoid tanning salons.
Use sunscreen.
Cover your skin before you go outside.
Dry mouth Stay hydrated. Apply lip balm.
Suck on sugar-free candy or ice chips.
Chew sugar-free gum.
Use a product specially designed to relieve dry mouth.
Practise good oral hygiene.
Dry nose Use a spray bottle containing a saline solution or gel specially designed to moisturize the nasal mucosa.
Keep the air in your home sufficiently humidified.
Drowsiness Avoid activities that require concentration, such as driving and precision work.
Take your medication at bedtime.
The drugs and pharmaceutical services featured on the website are offered by pharmacists who own the affiliated pharmacies at Familiprix. The information contained on the site is for informational purposes only and does not in any way replace the advice and advice of your pharmacist or any other health professional. Always consult a health professional before taking or discontinuing medication or making any other decision. Familiprix inc. and the proprietary pharmacists affiliated with Familiprix do not engage in any way by making this information available on this website.