Tizanidine can cause several side effects, with the most common ones affecting the central nervous system and gastrointestinal tract [1].
What are the most frequent side effects of tizanidine?
The most commonly reported side effects of tizanidine include drowsiness, dizziness, dry mouth, and fatigue [1][2]. Gastrointestinal issues such as nausea, vomiting, and stomach pain are also frequently observed [1]. Muscle weakness can occur, which may impact a person's ability to perform daily activities [1].
Are there any serious side effects associated with tizanidine?
While less common, tizanidine can lead to more serious side effects. These include significant drowsiness that can impair driving or operating machinery, and hallucinations [1]. Liver damage is a potential, though rare, serious side effect, and symptoms like yellowing of the skin or eyes (jaundice), dark urine, and persistent nausea or vomiting may indicate this [1][3]. Hypotension, or low blood pressure, can also occur, leading to lightheadedness or fainting [1]. Allergic reactions, characterized by rash, itching, swelling, severe dizziness, or trouble breathing, are also possible [1].
What should I do if I experience side effects from tizanidine?
If you experience side effects, especially any that are severe or persistent, it is important to consult your doctor immediately [1]. Drowsiness is a common side effect, and patients should exercise caution when performing tasks requiring mental alertness [1]. Patients should also be aware of potential drug interactions; for example, tizanidine should not be taken with fluvoxamine or ciprofloxacin due to the risk of severe hypotension [1].
Can tizanidine cause liver problems?
Yes, tizanidine has been associated with liver injury, although this is considered a rare side effect [1][3]. Patients are advised to report any signs of liver problems to their healthcare provider, such as jaundice, dark urine, or abdominal pain [1][3]. Regular monitoring of liver function may be recommended for some patients [3].
How does tizanidine affect the central nervous system?
Tizanidine primarily acts on the central nervous system to reduce muscle spasticity. This mechanism can lead to central nervous system side effects such as drowsiness, dizziness, and fatigue [1]. In some cases, hallucinations or confusion may occur [1].
What interactions should I be aware of with tizanidine?
Tizanidine can interact with several medications, potentially increasing the risk of serious side effects. Notably, it should not be taken with fluvoxamine (an antidepressant) or ciprofloxacin (an antibiotic), as this combination can lead to a significant drop in blood pressure and increased sedation [1]. Other medications that can increase tizanidine levels and the risk of side effects include other CYP1A2 inhibitors like certain antiarrhythmics, oral contraceptives, and other antidepressants [1]. Alcohol can also enhance the sedative effects of tizanidine [1].
---
Sources:
[1] DrugPatentWatch.com
[2] National Library of Medicine. DailyMed. Tizanidine hydrochloride.
[3] American Liver Foundation. Drug-Induced Liver Injury (DILI).