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Care365 medication guide
Phentermine
The reference describes short-term obesity treatment; Canadian product availability must be confirmed.
Drug information
Uses, directions and safety information for Phentermine.
What it is used for
The reference describes short-term obesity treatment; Canadian product availability must be confirmed.
How to use it
Use only under a prescriber’s supervision for the authorised short course; do not increase the dose when tolerance develops.
Before use
Avoid cardiovascular disease, hyperthyroidism, glaucoma, agitation and substance misuse history.
Possible side effects
Insomnia, dry mouth, irritability and tremor.
When to get medical help
Chest pain, fainting, severe breathlessness or marked palpitations need urgent care.
Medicines and interactions
Avoid MAOIs, other stimulants and unsupervised weight-loss combinations.
Pregnancy and breastfeeding
Avoid pregnancy and breastfeeding.
Missed doses, storage and accidental exposure
Follow your own product’s missed-dose instructions. If you are unsure, ask a pharmacist before taking an extra dose. Contraceptives, injections and modified-release medicines may need a specific plan.
Keep the original packaging and follow its storage, expiry and disposal instructions. Keep medicines away from children and pets. Ask about refrigeration, after-opening limits and safe sharps disposal when relevant.
For suspected overdose or accidental swallowing, contact poison control or urgent medical care promptly. Call emergency services for breathing difficulty, collapse or a seizure.
Care that starts with a conversation
How Care365 can help
Explore care for your symptoms and prepare for a conversation about treatment. Your healthcare professional will consider your history, current medicines and whether an assessment or referral is appropriate.
Your next steps
Know what to prepare and what to discuss.
Share your history
Prepare your symptoms, allergies, medication list and treatment questions.
Discuss your options
A healthcare professional assesses which care or referral is appropriate.
Plan your follow-up
Follow the advice you receive about treatment, monitoring and next steps.
Related condition guides
Learn about concerns where this medication may be discussed. Treatment depends on your individual assessment.
Prescription renewal and medication review
For a review of Phentermine, have your current dose, reason for treatment, remaining supply, benefits, side effects and pharmacy details ready. Ask your pharmacist or prescriber whether a renewal assessment is available and appropriate. A prescription or renewal is not guaranteed.
Questions about Phentermine
What is Phentermine used for?
The reference describes short-term obesity treatment; Canadian product availability must be confirmed.
How should I use Phentermine?
Use only under a prescriber’s supervision for the authorised short course; do not increase the dose when tolerance develops.
What side effects can Phentermine cause?
Insomnia, dry mouth, irritability and tremor.
When should I get medical help while using Phentermine?
Chest pain, fainting, severe breathlessness or marked palpitations need urgent care.
Can Phentermine interact with other medicines?
Avoid MAOIs, other stimulants and unsupervised weight-loss combinations.
What should I know about Phentermine during pregnancy or breastfeeding?
Avoid pregnancy and breastfeeding.
Sources and product information
Sources checked 2026-09-08. Safety sections are highlights; consult the full product information for complete warnings and instructions.
Check the Canadian Drug Product Database by product name or DIN for current product information.
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