Tizanidine, sold under the brand name Zanaflex among others, is a medication that is used to treat muscle spasticity due to spinal cord injury or multiple sclerosis. Effectiveness appears similar to baclofen or diazepam. It is taken by mouth.Common side effects of Tizanidine include dry mouth, sleepiness, weakness, and dizziness. Serious side effects may include low blood pressure, liver problems, psychosis, and QT prolongation. It is unclear if use in pregnancy and breastfeeding is safe. It is an α2-adrenergic agonist and how it works is not entirely clear.Tizanidine was approved for medical use in the United States in 1996. It is available as a generic medication. In 2019, it was the 92nd most commonly prescribed medication in the United States, with more than 8 million prescriptions. Medical uses
Tizanidine has been found to be as effective as other antispasmodic drugs and is more tolerable than baclofen and diazepam. Side effects
Side effects include dizziness, drowsiness, weakness, nervousness, confusion, hallucinations, strange dreams, depression, vomiting, dry mouth, constipation, diarrhea, stomach pain, heartburn, increased muscle spasms, back pain, rash, sweating, and a tingling sensation in the arms, legs, hands, and feet. Interactions
Concomitant use of tizanidine and moderate or potent CYP1A2 inhibitors (such as zileuton, certain antiarrhythmics (amiodarone, mexiletine, propafenone, verapamil), cimetidine, famotidine, aciclovir, ticlopidine and oral contraceptives) is contraindicated. Concomitant use of tizanidine with fluvoxamine, a potent CYP1A2 inhibitor in humans, resulted in a 33-fold increase in the tizanidine AUC (plasma drug concentration-time curve). For this reason both fluvoxamine and tizanidine should not be taken at the same time.
Remitting seronegative symmetrical synovitis with pitting edema (or sometimes RS3PE) is a rare syndrome identified by symmetric polyarthritis, synovitis, acute pitting edema (swelling) of the back of the hands and/or feet, and a negative serum rheumatoid factor. If no underlying disorder can be identified (idiopathic RS3PE), this entity has an excellent prognosis and responds well to treatment.RS3PE typically involves the joints of the extremities, specifically the metacarpophalangeal and proximal interphalangeal joints, wrists, shoulders, elbows, knees and ankles. It is more common in older adults, with the mean age between 70 and 80 years in most studies. It occurs more often in men than in women with a 2:1 ratio. It is unknown how common this condition is. Signs and symptoms
Individuals affected by RS3PE typically have repeated episodes of inflammation of the lining of their synovial joints and swelling of the end portion of the limbs. The arms and hands are more commonly affected than the legs and feet. Both sides are usually involved though RS3PE can affect only one side in certain cases. Causes
RS3PE is a constellation of symptoms that can be caused by many other conditions. Since there is no definitive diagnostic test, other conditions have to be ruled out before this rare condition can be diagnosed. The main differential diagnosis is polymyalgia rheumatica (PMR), although pain, stiffness and weakness at the level of the shoulders and pelvic girdle with associated systemic symptoms (fever, malaise, fatigue, weight loss) is more typical of PMR.