Varenicline is a drug that can help cigarette smokers stop smoking. Typically, the common side effects of the drug relate to the gastrointestinal tract and to the ability of the person to sleep soundly. Less common, but more severe possibilities include a low risk of mental disturbance or allergic reaction to the drug.
People who take vareniciline typically take it as by mouth as a tablet. Once or twice a day is the general treatment regime, and the person who is trying to stop smoking can take the drug for several months at a time. When a tablet has to go through the digestive system, side effects can begin there, and this is also the case for varenicline side effects.
Those taking it may find that the taste of foods and drinks changes while on the drug, such as a lessening in taste sensitivity, or an unpleasant taste in the mouth. The mouth may become drier than usual, and the person may become less or more hungry while taking the medication. Varenicline side effects on the stomach include a sensation of pain, or of being full and bloated. Heartburn and nausea may also occur, and the person may suffer vomiting.
Excess intestinal and stomach gas is another aspect of the varenicline side effects, and people on the drug can also experience constipation. Along with the gastrointestinal tract, the person may feel lethargic and have a general feeling of illness. General bodily weakness is also one of the commonest varenicline side effects, as are sleepiness and tiredness.
Apart from issues with the digestive tract, varenicline side effects also primarily affect sleep patterns of the patient. An inability to sleep, or waking up during the night, may occur, and the person can suffer from strange dreams or nightmares. Headaches are also included in the most common varenicline side effects.
Medical advice may be necessary if these usually mild varenicline side effects last for an extended period of time, or occur in severe attacks. As well as the most common side effects, varenicline also carries a risk of allergic reaction, like many other medications. Symptoms of an allergic reaction include problems breathing, and swelling of the face or other parts of the body. Varenicline may also cause potentially serious mental effects. Examples of these effects include contemplation of suicide, aggressive behavior and depression; immediate medical advice should be sought if any of these signs occur.