Skin Home > Common Reactions to OnabotulinumtoxinA
Common Side EffectsOnabotulinumtoxinA has been studied thoroughly in clinical trials. In these studies, the side effects that occur in a group of people taking the drug are documented and are then compared to those that occur in another group of people not taking the medicine. This way, it is possible to see what side effects occur, how often they appear, and how they compare to the group not taking the medicine.
In studies using onabotulinumtoxinA for cosmetic purposes (to improve the appearance of lines between the eyebrows), common side effects included:
- Droopy eyelids -- in up to 3 percent of people
- Nausea -- up to 3 percent
- Muscle weakness -- up to 2 percent
- Facial pain -- up to 2 percent
- Indigestion or heartburn -- up to 1 percent
- Tooth problems -- up to 1 percent
- High blood pressure (hypertension) -- up to 1 percent
- Eyelid swelling -- up to 1 percent.
In studies using the drug for medical conditions rather than cosmetic purposes, the following common onabotulinumtoxinA side effects were reported:
- Droopy eyelids -- in up to 20.8 percent of people
- Difficulty swallowing -- up to 19 percent
- Vertical misalignment of the eye (vertical deviation) -- up to 16.9 percent
- Upper respiratory infection (such as the common cold) -- up to 12 percent
- Neck pain -- up to 11 percent
- Headache -- up to 11 percent.
In studies of onabotulinumtoxinA for treating bladder problems, the most common side effects included:
- Urinary tract infection (UTI) -- in up to 24 percent of people
- Difficulty passing urine -- up to 17 percent
- Painful urination -- up to 9 percent
- Blood in the urine -- up to 4 percent
- Fatigue -- up to 4 percent.
Other common reactions (occurring in 2 to 10 percent of people) included:
- Flu-like symptoms, such as a fever and chills
- Back pain
- Runny or stuffy nose
- Soreness at the injection site
- Dry mouth
- Bleeding at the injection site
- Sore throat
- High blood pressure (hypertension)