Tizanidine: Uses, Mechanism of Action, Side Effects, Interactions, Precautions and Warnings

It is a prescription medication used to relieve spasms and increase muscle tone caused by multiple sclerosis, stroke, among others.

Tizanidine belongs to a group of medications called skeletal muscle relaxants, which work by decreasing the action in the brain and nervous system to allow the muscles to relax.

This medicine comes in the form of tablets and capsules and is taken up to 3 times a day, with or without food. However, it should always be taken consistently with food or without food.

Common side effects of Tizanidine include dry mouth, weakness, drowsiness and dizziness.

Applications

Tizanidine is used to control muscle spasms. Symptoms may include muscle tension, pain or stiffness.

This medication is often used for people with multiple sclerosis , spinal cord injury, or muscle spasticity.

Mechanism of action

Tizanidine belongs to a class of medications called alpha-2-adrenergic agonists.

It reduces the activity of the nerves in the spinal cord that control the muscles. This helps reduce muscle spasms.

Side effects

Serious side effects have been reported with Tizanidine.

Most common side effects:

The most common side effects of Tizanidine may include:

  • Dry mouth.
  • Fatigue.
  • Weakness.
  • Dizziness.
  • Urinary tract infection.
  • Constipation .
  • Vomiting
  • Problems to talk.
  • Runny nose.
  • Sore throat.
  • Problems with the eyes

Serious side effects:

Extremely low blood pressure:  Symptoms may include:

  • Dizziness or lightheadedness, especially when standing after sitting or lying down.

Hallucinations: Symptoms may include:

  • See things that are not real.

Illusions: Symptoms may include:

  • Believe things that are not real.

Liver damage: Symptoms may include:

  • Increased bleeding or bruising
  • Yellow coloring of the skin or the whites of your eyes.

Interactions with other medications

Tell your doctor about all the medications you take, including prescription and over-the-counter medications, vitamins and herbal supplements. Especially, tell your doctor if you take:

  • Alcohol.
  • Baclofeno (Lioresal).
  • Benzodiazepinas como Triazolam (Halcion), Alprazolam (Xanax) y Diazepam (Valium).

Drugs that block the CYP1A2 enzyme such as:

Do not take the following medications with Tizanidine. When used, these drugs can cause dangerous effects in the body. Examples of these medications include:

Fluvoxamine and ciprofloxacin: The use of these medicines with Tizanidine can cause very low blood pressure. It can also cause increased drowsiness or decreased muscle control.

Other alpha-2 agonist drugs: such as Clonidine, Methyldopa, Guanfacine or Guanabenz. The use of these medications with Tizanidine can cause very low blood pressure.

Drugs that increase the risk of side effects of Tizanidine:

Taking Tizanidine with certain medications increases the risk of side effects of Tizanidine. This is because the amount of Tizanidine in your body increases. Examples of these medications:

Zileuton: Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Certain antibiotics called Fluoroquinolones: (other than Ciprofloxacin), such as Levofloxacin, Moxifloxacin, or Gemifloxacin. Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Some drugs used for heart rhythm: such as Mexiletine, Amiodarone, Propafenone or Verapamil. Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Antacids such as Cimetidine or Famotidine: Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Oral contraceptives: Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness. The use of oral contraceptives with Tizanidine is not recommended.

If these medicines are to be used together, your doctor may prescribe a single dose of 2 mg of Tizanidine. Then they can slowly increase the dose by 2-4 mg per day.

Acyclovir: Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Ticlopidine: Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Benzodiazepines: as Alprazolam, Lorazepam or Diazepam. Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Opioids: as Morphine, Methadone or Oxycodone. Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Certain antidepressants: such as Amitriptyline, Nortriptyline or Protriptyline. Increased side effects may include decreased blood pressure, decreased heart rate or extreme drowsiness.

Interactions with food:

Drugs can interact with certain foods, and this can be harmful. Know that your doctor can suggest that you avoid certain foods. However, in the case of Tizanidine, there are no specific foods that you should eliminate from your diet.

Precautions

Serious side effects with Tizanidine have been reported, including:

Rebound hypertension: ( high blood pressure ) and tachycardia (rapid heart rate). Do not stop taking Tizanidine suddenly, as hypertension and tachycardia may occur.

Liver damage: This may occur with the use of Tizanidine, but it has been shown to resolve once the use of this medication is stopped.

It is recommended that liver function monitoring be done during the first 6 months of treatment and periodically thereafter.

Low blood pressure : There is a possibility that Tizanidine may lower your blood pressure. Use caution when standing from a sitting position, as dizziness may occur due to decreased blood pressure.

Anesthesia:

Important Consideration: Since Tizanidine can cause dizziness and drowsiness, do not drive or operate heavy machinery until you know how Tizanidine affects your health.

Warnings

The oral tablet of Tizanidine comes with several warnings.

Do not take Tizanidine if you:

  1. You are taking medications that are strong blockers of CYP1A2 medications, including Fluvoxamine and Ciprofloxacin.
  2. You have liver problems
  3. He has kidney problems.
  4. You are allergic to it or any of its ingredients.
  5. Are pregnant or breastfeeding

Low Blood Pressure Warning: Tizanidine can cause very low blood pressure that causes dizziness or fainting. To help reduce this risk, your doctor may prescribe the lowest dose of this medication that is right for you.

If you already take medications that lower blood pressure, your doctor can control your blood pressure more often.

Liver damage warning: Tizanidine may cause liver damage. If you have liver disease, talk to your doctor to find out if this medication is safe for you.

If you take this medication, your doctor may control you for changes in liver function.

Hallucinations or delusions warning: Tizanidine can cause visual hallucinations (see things that are not real). It can also cause delusions (believe things that are not real). If you have any of these side effects, stop taking Tizanidine and call your doctor immediately.

Allergy warning:

Tizanidine can cause a severe allergic reaction. The indications of this can be:

  • Difficulty breathing.
  • Having Itching
  • Swelling of throat or tongue.

Note: If you have ever had an allergic reaction to this medicine, do not do it again because taking it again could be fatal and cause death.

Interaction with alcohol:

The use of alcohol-containing beverages increases the amount of Tizanidine in your body. This can cause an increase in side effects.

Warnings for people with certain health conditions:

People with decreased liver function: Talk to your doctor about whether Tizanidine is safe for your health.

If you take this medication, your doctor may give you a lower dose. In addition, he must control his liver function at the beginning of treatment. They can check it again one month after their maximum dose has been prescribed.

People with decreased kidney function: Talk to your doctor about whether Tizanidine is safe for you.

If you take this medication, your doctor may give you a lower dose. In addition, he will observe the accumulation of too much Tizanidine in his body. Symptoms may include dry mouth, dizziness or drowsiness.

Warnings for different groups:

Pregnant women: Tizanidine is a category C drug in pregnancy. This means two things:

Research in animals has indicated adverse effects for the fetus when the mother takes this drug.

However, you should know that there have not been enough studies in humans to be sure how Tizanidine might affect the baby.

This medicine should only be used if the potential benefit justifies the potential risk to the fetus. Call your doctor if you become pregnant while taking this medication.

For women who are breastfeeding: It is not known if Tizanidine passes into breast milk and causes side effects in a child who is breastfed.

Talk to your doctor if you breast-feed your child. You may have to decide whether to stop breastfeeding or stop taking this medication.

Older people: the kidneys of older adults do not work as well as they used to, and this can cause the body to process drugs more slowly.

As a result, more than one medication stays in your body longer.

For children: This medicine has not been studied in children therefore it should not be implemented in people under 18 years of age.

Administration

This medicine comes in the form of tablets and capsules and is taken up to 3 times a day, with or without food.

You can sprinkle the contents of the capsule on a soft food, such as applesauce or pudding. Be sure to consume the contents of this mixture completely.

The body’s ability to absorb Tizanidine if taken with food differs if taken without food. Be sure to be consistent and take only with food or without food.

The change between the two forms will cause a difference in the therapeutic levels of Tizanidine in the body.

Alcohol can intensify some of the side effects of this medication.

Dosage:

Take Tizanidine faithfully as ordered by your doctor. The recommended dose will be based on the following:

  1. How you respond to this medication
  2. Other medications you are taking.
  3. Your liver function
  4. Your kidney function

This dosing information is for oral tablets of Tizanidine. Your dosage, form of the remedy and how many times you take that medicine will abide by:

  • How serious is that condition?
  • The condition that will be treated.
  • The age you have.
  • Other medical circumstances that you present.
  • How your body reacts the first dose of Tizanidine.

Dosage for muscle spasms:

Dose for adults (over 18 years old):

Typical start dose: 2 mg every 6-8 hours as needed.

Increasing the dose: your doctor or health specialist can increase your dose by 2-4 mg until your conditions are controlled. They will wait 1 to 4 days between each increment.

Maximum dose: 3 doses in 24 hours.

Dosage for children (ages 0-17 years):

This medicine has not been studied in children therefore it should not be implemented in people under 18 years of age.

Higher dosage (over 65 years old):

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, more than one medication stays in your body longer.

Your doctor may start with a low dose or a different dosing schedule. This can help prevent levels of this drug from accumulating too much in your body.

Based on the dosage:

Take as indicated:

The oral tablet of Tizanidina is used for long or short term treatments. It leads to serious risks if you do not take it as prescribed.

What happens if I stop taking Tizanidine suddenly or I do not take it anymore?

If you block the treatment unexpectedly, you will be at risk of having withdrawal symptoms . This risk is greater if you have been taking high doses of the medication or if you take it for a prolonged period.

Withdrawal symptoms may include:

  • High blood pressure.
  • Accelerated heart rate.
  • Muscle spasms worsened.

If you decide to stop taking this medication, your doctor should slowly lower your dose by 2-4 mg per day. If you do not take this medication, your muscle system may not improve.

Remember that if you miss doses or do not take the medication as scheduled, your medication may not work as well or may stop working completely.

Note: If you miss too many doses, you may have withdrawal symptoms. If you take too much, you could have dangerous levels of the drug in your body.

Symptoms of an overdose of this medication may include:

  • Exhausted.
  • Confusion.
  • Incrise of cardiac frecuency.
  • Severe decrease in blood pressures.
  • Slow breathing

If you think you have taken too much of this medication, call the reserved emergency number for your region.

What do I do if I miss a dose?

Take your dose as soon as you remember it. But if you remember it a few hours before your next scheduled dose, take only one. Never try to catch up by taking two doses at a time. This could cause dangerous side effects.

How to know Tizanidine is really working?

You must have fewer symptoms of muscle spasms. These symptoms may include muscle tension, pain or stiffness.

Interesting information about Tizanidine

How to store Tizanidine?

  • Store Tizanidine at room temperature between 15-30 ° C (59-86 ° F).
  • Dispense in childproof lockable containers.
  • Keep Tizanidine and all other medicines out of the reach of children in the home to avoid risks of ingestion.

Highlights of Tizanidine:

The oral tablet of Tizanidine is available as a generic and brand-name drug.

Brand: Zanaflex.

Tizanidine is used to control muscle spasms. It is often used for people with multiple sclerosis, spinal cord injury or muscle spasticity.

Important considerations

Consider these considerations if your doctor prescribes Tizanidine orally:

  • You can take Tizanidine with or without food. But it should be consistent. Take it the same way every time.
  • You can cut or crush the tablets.
  • Do not store this remedy in cool places, such as bathrooms.

When you travel:

You do not have to worry about airport X-ray machines, because they can not harm your drug. However, you may need to show your pharmacy label to the airport staff.

Therefore, always have the original box with the label and the recipe with you. Do not place this remedy in the glove compartment of your car and do not leave it in it either.

Always take your medication with you. When flying, never put it in a checked bag. Keep it in your best handbag.

Be sure to avoid doing this when it is very cold or very hot outside.

Do not change between the forms, capsule and tablet of Tizanidine:

Once you start taking this drug, you should not change it or the form of administration unless your doctor recommends it.

Clinical monitoring:

You and your doctor must control certain health problems. This can help ensure that you remain safe while taking Tizanidine. These problems include:

Kidney function: Blood tests can check how well your kidneys are working. If your kidneys are not working well, your doctor may reduce the dose of this medicine.

Liver function: Blood tests can check how well your liver is working. If your liver is not working well, your doctor may reduce the dose of this medication.

Blood pressure: Your doctor may check your blood pressure to make sure it does not go too low while taking Tizanidine.