There are two primary prescription drugs that can help you to quit smoking; Zyban and Champix. You must be aged 18 or over to use them and they are only available via your doctor.
They are only available via prescription because they can cause adverse side effects for people with existing medical conditions. For the same reason, they cannot be used if you are pregnant
Zyban is the brand name for a drug called Buproprion Hydrochloride and outside of the UK, it is also known as Wellbutrin, Voxra, Budeprion and Aplenzin.
It works by reducing your craving for nicotine.
The course of Zyban tablets are taken 2 weeks prior to quitting smoking. After you quit, the tablets will continue to be taken for a another 8-10 weeks.
Champix (or Chantix in the US) is the brand name for a drug called Varenicline.
It works by activating the same receptors that nicotine does, thereby imitating a mild nicotine ‘hit’. This reduces the cravings you have for cigarettes.
Like Zyban, Champix is a tablet that is taken regularly 2 weeks before quitting smoking. After quitting, the course continues for another 8-10 weeks.