What Are the Most Common Acetylcysteine Side Effects?

While they are typically mild and short-lived, there are a number of common acetylcysteine side effects that patients may experience when taking the drug to break up mucous. It can cause the skin to feel cold and clammy. A mild fever may develop, but should go away within a day or so. Patients may also feel nauseous or vomit when they first start taking acetylcysteine, but this should also resolve itself fairly quickly as the body becomes accustomed to the drug. Other commonly reported issues include a runny nose, drowsiness, and irritation of the tissues in the mouth.

One of the most frequent acetylcysteine side effects is a feeling of clamminess. The patient’s skin may feel moist, cold, or sticky, and appear pale. Although it may be unpleasant, the sensation is not dangerous and often goes away after a short period of time.

Another of the acetylcysteine side effects that is often reported is a brief, mild fever when a patient begins the medication. A shift in body temperature of a degree or two is quite common and should not be cause for alarm, though it may cause an achy feeling or chills. A very high fever, or one that persists for more than 24 hours, may indicate a more serious problem and should be reported to a doctor.

Acetylcysteine can also cause a brief period of stomach upset and nausea. Some patients may even vomit if the feeling is severe enough. As with the previously mentioned acetylcysteine side effects, this should subside relatively quickly as the body acclimates to the drug.

Runny nose is one of the most common acetylcysteine side effects. The drug is typically used to help liquefy and break up mucous, allowing patients with diseases like emphysema, chronic bronchitis, and tuberculosis to clear it from his or her lungs more easily. This effect also impacts the mucous membranes in the sinuses, causing them to drain more than normal.

Feelings of drowsiness can often be one of the acetylcysteine side effects. Patients should use caution when taking the drug, as it may impair their ability to drive or perform other activities requiring them to be alert. Many patients also complain that inhaling acetylcysteine irritates the mucous membranes on the inside of their mouths. Rinsing the excess medication out after taking a dose may help minimize this problem.