Varenicline

Varenicline is used to help adults stop smoking.

You should be aware that your chance of success when using stop-smoking therapies is increased when you are motivated to stop smoking, and when the therapy is used alongside other help and advice. Advice, support, and further information is available from your doctor and pharmacist.

Can I buy Varenicline online?

The Online Clinic can prescribe Varenicline to help patients give up smoking. Please click on the button below to start your free online consultation with one of our GPs.

What is Varenicline?

Varenicline is the active substance in this medicine.

Varenicline works by attaching to nicotine receptors in the brain, where it competes with nicotine for attachment sites on the nicotine receptors. Varenicline works on nicotine receptors in two ways:

• By activating the receptors, varenicline reduces your craving for a cigarette and the effects of withdrawal when you go without; and
• By partly blocking nicotine from activating the receptors, varenicline reduces your pleasure from smoking and your desire to continue.

How to use Varenicline

Varenicline is available as film-coated tablets in two strengths. Usually, treatment starts with the white tablets that contain 0.5 mg varenicline tartrate, followed by the light blue tablets that contain 1 mg varenicline tartrate. The tablets are swallowed whole with water, either with or without food. The intoxicating effects of alcohol may be increased.

Before starting treatment, decide when you want to quit smoking. This can be between Day 8 and Day 14 of treatment or a day of your choice within 5 weeks after the treatment start date. Write your chosen quit date on the pack so that you do not forget.

The treatment course is 12 weeks.

• Day 1 to day 3: Take one white 0.5 mg varenicline tablet once a day.
• Day 4 to day 7: Take one white 0.5 mg varenicline tablet twice a day (one in the morning and one in the evening), at around the same time every day.
• Day 8 to day 14: Take one light blue 1 mg varenicline tablet twice a day (one in the morning and one in the evening), at around the same time every day.
• From day 15 to the end of treatment (12 weeks): Take one light blue 1 mg varenicline tablet twice a day (one in the morning and one in the evening), at around the same time each day.

A second 12-weeks treatment (1 mg varenicline tablets twice a day) may be recommended to help:

• stop those who have quit smoking after 12-weeks treatment from smoking again.
• those who could not stop, but reduced smoking during the first 12-weeks treatment and stopped by the end of the 12-weeks treatment.

The doctor may reduce the dose from 1 mg to 0.5 mg twice a day if the medicine is not tolerated or causes side effects.

You are at greatest risk of restarting smoking immediately following the end of treatment. The doctor may therefore gradually lower the dose at the end of treatment.

Seek medical advice or go to a hospital casualty department immediately if you take more varenicline than instructed. If you forget to take varenicline, then take the forgotten tablet when you remember. However, do not take the forgotten tablet if it is only 3-4 hours before your next dose. Take the next dose only and do not take the missed tablet as well.

Who can use Varenicline?

Varenicline is prescribed for adults only. Discuss with a doctor your pregnancy or your intention to have a baby or breastfeed before taking this medicine.

Anybody with an allergy to varenicline or any of the other tablet constituents should not use varenicline.

Before treatment tell your doctor if you have or have a history of psychiatric disorder, seizures, or epilepsy. During treatment contact your doctor if symptoms develop or worsen, particularly if you have new or worsening blood vessel or heart problems.

Check that varenicline does not make you feel dizzy, sleepy, or temporarily lose consciousness before you drive, operate machinery or participate in any risky activities.

It is important to inform your doctor of medicines you are taking, might take, or have recently taken before starting varenicline, including any other smoking cessation therapies. Cigarette smoke contains many harmful chemicals, including nicotine and carbon monoxide. When you stop smoking (with or without the help of varenicline), your other medicines may be affected and their dose may need to be adjusted, including insulin, warfarin, and theophylline. Cimetidine should not be taken by people with severe kidney disease who are taking varenicline, as it may raise the level of varenicline in the blood.

Varenicline side effects

Some people temporarily experience the desire to smoke, irritability, depression, and/or poor sleep when stopping varenicline.

While rare, stop taking varenicline and get immediate medical help if you have signs and symptoms of an allergic reaction (e.g., face, mouth, throat or swelling, difficulty breathing). Contact your doctor if you experience symptoms of agitation, low mood, suicidal thoughts or behaviour, or other worrying behavioural changes; and/or serious skin rashes with peeling or blistering.

More than one in 10 people experience nausea, headache, abnormal dreams, and inflammation of the nose and throat. Less common are gut problems; changes in appetite and the way things taste; cough and chest infections; feeling tired, sleepy, and dizzy; and/or aches and pains.

Other signs and symptoms may occur but are uncommon, and include restlessness, feeling of panic, poor concentration, tremor, seizures, muscle spasms, rapid heart rate and palpitations, chest discomfort, raised blood pressure, heart attack, inflammation of the respiratory tract, increased sweating, weakness, sexual dysfunction or menstrual changes and/or urinary disorders. Rarely, people experience slow thinking, psychosis, difficulty with coordination, muscle tension, eye disorders and vision disturbances, irregular heartbeat or heart rhythm, diabetes, and cyst.

References

Varenicline 0.5 mg and 1 mg film-coated tablets. Browne & Burke UK Ltd., Hounslow TW4 5DQ, UK. Apr 2024.

Resources

NHS Quit Smoking:
https://www.nhs.uk/better-health/quit-smoking/

CBQ:
https://cbqmethod.com/

Action on Smoking and Health:
https://ash.org.uk/resources/view/stopping-smoking