Varenicline

What changes when you take it

Anyone who has tried to quit knows the loop: the craving hits, the cigarette fixes it. Varenicline interferes at both ends. It attaches to the receptors nicotine uses and switches them on only partly, which takes the edge off cravings and the restless first days, and it leaves a cigarette with less to give. The tablet contains no nicotine. It is made for adults who have decided to stop.

A twelve-week course, week by week

Week one is the build-up, and you carry on smoking through it: 0.5mg once a day for three days, then 0.5mg morning and evening for four more. From day eight the dose is 1mg twice a day, the dose that runs to the end, and the quit date falls about a week after the first tablet. Twelve weeks is the usual course, with a second twelve possible for people who want help staying off cigarettes. Tablets go down after a meal with a full glass of water, at about the same times each day. Some prefer a quit date a few weeks in, or cutting down gradually across the twelve.

Champix and Varenicline

Both packs on this page hold the 0.5mg and 1mg tablets a course needs, so the opening week and the maintenance dose arrive together. Champix is the brand name for the ingredient; Varenicline is the same medicine sold under its own name, with the same strengths in the box. Either way, the tablets belong to the shop's stop-smoking category. Keep the blister strips in a dry cupboard, out of sunlight.

Side effects, the common and the serious

Nausea is the one most people mention, worst while the dose is still rising and softened by taking tablets after food. Headache, broken sleep with vivid dreams, constipation and wind turn up as well. Some people feel drowsy, dizzy or unable to concentrate, so wait to see how it affects you before driving or using machinery. Agitation, low mood or thoughts of self-harm are the serious ones, and the tablets should be stopped if they appear. Swelling of the face, lips or throat after a dose needs urgent treatment. Seizures and serious skin reactions are rare.

Using it with patches or gum

Some people quit with a patch on as well as the tablet, and that is allowed: nicotine replacement feeds the receptor nicotine, while varenicline occupies the same receptor and blunts the reward from a cigarette. Bupropion works on the urge another way. Varenicline leaves the body through the kidneys almost unchanged, so it clashes with very few medicines; only severe kidney disease calls for a lower dose.