Healthy Living

Side Effects of Flexeril and How to Minimize Them

Side Effects of Flexeril and How to Minimize Them

Generic Name: Cyclobenzaprine

Brand Name: Amrix, Flexeril, Fexmid.

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What Is Flexeril?

Flexeril is a muscle relaxant that works by blocking the nerve impulses or pain sensations that are sent to the brain. Flexeril can be used as a short-term treatment for healing muscle spasms.

Patients suffering from fibromyalgia have reported a reduction in muscle spasms and pain after taking Flexeril.

Flexeril, mostly taken at night, is known to reduce pain and other symptoms. Patients have reported improvements in pain, tenderness, fatigue, mood, and sleep while taking this medication. However, most studies only used low doses of Flexeril which ranged from 1mg to 4mg doses. There has been concern that higher doses of Flexeril can lead to an increase in fatigue.

Can Anyone Use Flexeril?

  • Individuals who have recently suffered a heart attack should avoid using Flexeril.
  • Those who have heart problems such as heart blockage, congestive heart failure, or an overactive thyroid should also avoid taking Flexeril.
  • Flexeril should not be taken with alcohol. Mixing alcohol with Flexeril may cause drowsiness or other side effects.
  • Individuals who are above the age of 65 years should avoid taking this drug. Flexeril has a higher risk of causing extreme side effects in elderly patients.
  • For individuals who have been taking a MAO inhibitor, it is advisable to use Flexeril 14 days after discontinuing the drug. Some of these MAO inhibitors include tranylcypromine, selegiline, isocarboxazid, and phenelzine. Taking both Flexeril and a MAO inhibitor together can cause life-threatening side effects. It is important that the MAO be completely out of the patient’s system before starting Flexeril.

Before Usage

It is important to inform your doctor if:

  • You have been using an MAO inhibitor within the past 14 days.
  • You have been suffering from heart related medical conditions such as heart blockage, heart attack, or overactive thyroid.
  • You are allergic to any of the contents or ingredients present in Flexeril.
  • You are allergic to any foods, medicines, or other substances.
  • You are currently taking other medications, vitamins, dietary supplements, or herbal supplements.
  • You are pregnant, planning to become pregnant, or breastfeeding.

Usage and Dosing 

Flexeril should be taken exactly as prescribed by the doctor. Avoid taking Flexeril in larger or smaller doses without first consulting your doctor.  

Do not prolong the use of this medication without recommendation from the doctor. Flexeril should be taken along with a full glass of water. Take this medicine orally by mouth. It can be taken with or without food. There are various factors which a doctor will consider before prescribing your dose of Flexeril. Some of these factors include:

  • Age
  • Current or past medical conditions
  • Severity of the condition for which you are being treated
  • Other medications, vitamins, herbs, or dietary supplements that are being taken.

Remember that Flexeril alone will not help in treating your condition. This medication should be combined with plenty of rest, physical therapy, or some other measure for pain relief. Flexeril should be stored at room temperature and away from light, heat, and moisture.

If you miss a dose of Flexeril, take it as soon as you remember. However, if it is already almost time for you next dose, skip the missed dose and continue on with your normal dose routine. Do not take a double dose. Taking a double dose of Flexeril may cause an overdose, which can be fatal. The symptoms of Flexeril overdose are:

Flexeril is only for short-term use. Normally, this medication is prescribed for no more than three weeks. Do not stop or reduce the dosage of this medication if symptoms begin improving. If the medical condition persists or worsens after three weeks, consult your doctor.

Drug Interactions 

Certain drugs are known to have a negative interaction with Flexeril. Some of these drugs include:

  • Glycopyrrolate (Robinul)
  • Tramadol (Ultram)
  • Bronchodilators such as tiotropium or ipratroprium
  • Mepenzolate (Cantil)
  • Guanethidine (Ismelin)
  • Antihistamines such as cetirizine and diphenhydramine
  • Drugs that increase serotonin levels such as ecstasy or street drugs.
  • Medicines which cause drowsiness such as cough medicines or opioid medicines.
  • Medications that treat urinary issues such as oxybutynin, solifenacin, darifenacin, and tolterodine.
  • MAO inhibitors should not be taken for at least two weeks before starting Flexeril. The doctor can guide you on when to start or stop the medications.
  • Medications related to irritable bowel syndrome such as Hyoscyamine, dicyclomine, or propantheline.

Side Effects 

Symptoms of an allergic reaction to this medication include breathing difficulties, hives, and swelling of the face, tongue, lips, or throat. If these symptoms are mild, there is no need to be alarmed. However, it is important to consult your doctor immediately if your symptoms worsen or last for an extended period of time.

Below are the serious side effects associated with Flexeril:

  • Fainting
  • Uneven heartbeats
  • Easily bruising or bleeding
  • Loss of appetite
  • Headache which tend to worsen
  • Chest pain or tightness
  • Unusual weakness
  • Fatigue
  • Lack of coordination
  • Excessive sweating
  • Numbness in various parts of the body
  • Nausea
  • Convulsions
  • Blurry vision or problems with eyesight
  • Problems with speech
  • Problems with balance
  • Stomach pain
  • Dark colored urine
  • Yellowing of the skin and eyes
  • Varied racing thoughts and behavior
  • Pain that spreads to other parts of the body such as shoulders and arms.

The common side effects of Flexeril are:

The rare, but severe, side effects of Flexeril treatment are:

  • Heart rhythm abnormality
  • Bronchospasm
  • Mental changes leading to depression
  • Increase in heartbeat
  • Abnormal liver functions
  • Pain or difficulty urinating
  • Fainting spells
  • DRESS syndrome
  • Itchy skin
  • Large hives
  • Skin inflammation due to allergy
  • Skin rash
  • Trouble breathing or slow breathing
  • Unable to coordinate body movements
  • Yellowing of the skin or eyes
  • Abnormally low blood pressure
  • Serotonin syndrome
  • Unable to empty the bladder even after repeated attempts

Rare side effects of Flexeril that are less severe include:

  • Acne
  • Digestive problems
  • Slurred speech
  • Sweating profusely
  • Signs of agitation
  • Headache
  • Insomnia
  • Inability to pay attention or focus
  • Vomiting
  • Pounding heartbeat
  • Loss of taste
  • Intestinal or stomach irritation
  • Abnormal lack of energy
  • Nervousness
  • Tingling sensation in the hands and feet
  • Ringing sound in the ears
  • Muscle twitching
  • Widening of blood vessels
  • Stomach cramps

Minimizing Flexeril Side Effects 

  • One of the best ways to minimize the side effects of Flexeril is to consume this medicine exactly as prescribed by the doctor.
  • Drug interactions are often the cause of major side effects; therefore, it is important to minimize these interactions. Inform your doctor of any other prescription medications, over the counter drugs, or supplements that you are taking.
  • Avoid consuming alcohol while taking Flexeril.
  • Inform your doctor of any past or present medical conditions.
  • Avoid taking Flexeril for longer than the recommended duration.
  • Do not exceed the dose of Flexeril that was recommended by your doctor.

Key Takeaways

  • Normally, this medication is prescribed for no more than three weeks.
  • Individuals who have recently suffered a heart attack should avoid using Flexeril.
  • Patients suffering from fibromyalgia have reported a reduction in muscle spasms and pain after taking Flexeril.