> Western Medicines > Varenicline


Chinese name:

What is Varenicline for?

Varenicline belongs to a class of medication called nicotinic receptor partial agonists. It works by decreasing the effects of withdrawal symptoms and reducing smoking satisfaction. It is indicated as a first-line aid to smoking cessation treatment.

How to use it?

Varenicline is taken orally as tablets.


Patients should first choose a quit date:

  • a fixed quit day one week before treatment starts (e.g. start Varenicline, then quit on day 8), or
  • a flexible quit day (e.g. start Varenicline, then quit between days 8-35), or
  • (for patients who are sure that they are not able or willing to quit abruptly), a gradual quit date (e.g. start Varenicline and reduce smoking by 50% by week 4, reduce an additional 50% by week 8, and continue reducing with a goal of complete abstinence by week 12)

Below is the recommended dosing schedule.

  • Day 1-3: 0.5 mg once daily
  • Day 4-7: 0.5 mg twice daily
  • Thereafter: 1 mg twice daily
    (For severe renal impaired patients, start 0.5 mg once daily, up to 0.5 mg twice daily as maintenance)

The duration of treatment is 12 weeks. For patients who have successfully stopped smoking after the whole treatment, an additional course of 12-week treatment is recommended to further increase the likelihood of long-term abstinence.

What are the side effects of Varenicline?

Common side effects of Varenicline include nausea, abnormal dreams, constipation, flatulence, and vomiting.

Who should not take Varenicline?

  • People who are allergic to Varenicline or any component of the formulation.

Pharmacist Tips:

  • If you have ever had depression or other mental health problems, talk with your doctor before using this drug.
  • Avoid drinking alcohol during treatment.
  • Do not drive or operate machinery until you know the effect of the medicine.
  • When you stop smoking, other drugs may be affected with or without using Varenicline. Talk with your doctor if you are taking any drugs.
  • When you stop smoking, you may experience withdrawal symptoms with or without using Varenicline, such as depressed mood, frustration, urge to smoke, restlessness, and trouble sleeping.

Common dosing schedule:

  • Varenicline should be taken after eating with a full glass of water.

This schedule is for reference only, adjustments may be made according to individual needs.


Some common medications Varenicline may interact with:

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Varenicline in Hong Kong?

In Hong Kong, Varenicline is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.


For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at https://www.drugoffice.gov.hk

Need more information?

For detailed information about the use of Varenicline in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.

Brands in Hong Kong
Available dosage
  • 0.5mg / 1mg / 0.5mg+1mg (Tablets)
Drug class
Drugs In Substance Dependence
Sub class
Nicotinic Receptor Partial Agonists
Other drugs in same class