Dr. Donald Farquhar, MD, FRCPC, is a board-certified respirologist with over 15 years of experience diagnosing and treating the full spectrum of lung disorders.

Trained at the University of Toronto and the Mayo Clinic, Dr. Farquhar is known for his warm bedside manner, evidence-based approach, and advocacy for preventive care.

His clinical interests include chronic obstructive pulmonary disease (COPD), asthma, interstitial lung disease, and pulmonary rehabilitation.

When he is not in clinic, he contributes to clinical research on inhaled therapeutics and mentors medical residents at Western University.

Old North Lung is an independent, patient-centered clinic located in London’s historic Old North district.

Our mission is to make world-class respiratory care accessible and understandable.

Every visit is anchored in clear communication, shared decision-making, and respect for your time.

The clinic features on-site spirometry, a comfortable infusion suite, and fully accessible examination rooms.

Your first visit lasts about 60 minutes.

We begin with a detailed health history and review of prior test results, followed by a focused respiratory examination.

When needed, in-office spirometry or FeNO testing helps refine the diagnosis on the same day.

Please bring:

Should further testing be required—such as high-resolution CT scanning, full pulmonary function testing, or sleep studies—our administrative team will coordinate bookings on your behalf and confirm the date, time, and location by phone and secure email.

Written instructions and preparation tips are always provided.

Before you leave the clinic, we will schedule any necessary follow-up visits to review results or adjust your treatment plan.

Virtual appointments are available for stable patients who live outside the city.

Comprehensive consultation letters—including test results and treatment recommendations—are sent to your family physician or nurse practitioner within 48 hours of your visit.

This ensures continuity of care and avoids duplicate testing.

We use Ocean e-Referrals for secure messaging and appointment reminders.

You may also reach us by telephone during business hours.

Non-urgent questions are answered within one business day.

For most inhalers and long-term medications, please ask your pharmacy to fax a renewal request at least one week before you run out.

Controlled medications require an in-person or virtual review every three months.