Flexeril is a type of medicine called cyclobenzaprine. Doctors give it to you when your muscles are hurting, maybe from lifting something heavy or playing sports. It helps your muscles relax, and it is used along with other things like resting and doing exercises.
Cyclobenzaprine was made in a lab in 1961, and people started using it as medicine in 1977. At first, scientists thought it could be used to make people feel less sad, like some other medicines, but it is different from one called Amitriptyline because of a tiny change in its structure.
Doctors usually say you should only take medicines like Flexeril for up to three weeks. After that, they might not help with muscle problems, and they could even lead to some serious issues like falls, broken bones, accidents while driving, or even problems with using the medicine too much or getting very sick from it.
So, it is important to follow the doctor’s advice and not use it for too long.
Why Was Flexeril Discontinued
Flexeril, the brand name, is no longer sold in the US because the company that makes it, Merck & Co. Inc., decided to stop selling it for business reasons. However, there are still other versions of the same medicine with different names, like Amrix and Fexmid, that you can get.
The medicine called Cyclobenzaprine, which is in Flexeril, was allowed to be used as a medicine in the US in 1977. In 2019, it was one of the most commonly prescribed medicines in the US, with over 15 million prescriptions. However, you cannot get it in the United Kingdom since 2012.
Using Flexeril in the wrong way can be very dangerous and sometimes even life-threatening. It’s supposed to be used for a short time, but some people use it for a long time, and it’s given to groups of people who might be at risk of having problems like taking too much or having bad reactions to it.
What should I discuss with my healthcare provider before taking cyclobenzaprine
Before taking cyclobenzaprine, talk to your doctor if:
You are allergic to it, or if you have:
- Problems with your thyroid
- Heart issues like an irregular heartbeat or heart failure
- Recently had a heart attack
- If you are younger than 15 years old, you should not use cyclobenzaprine.
Do not take cyclobenzaprine if you have used a medicine called an MAO inhibitor in the past 14 days. MAO inhibitors include drugs like isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine. Mixing them with cyclobenzaprine can be very dangerous.
Some medicines can mix with cyclobenzaprine and create a serious problem called serotonin syndrome. Make sure your doctor knows if you take other drugs like ones that give you energy, painkillers, natural remedies, or drugs for feeling sad, mental issues, Parkinson’s disease, bad headaches, bad infections, or to stop feeling sick. Talk to your doctor before you change how or when you take your medicines.
Tell your doctor if you have ever had:
- Problems with your liver
- A condition called glaucoma
- A big prostate
- Troubles peeing
We are not sure if this medicine can harm an unborn baby, so tell your doctor if you are pregnant or planning to have a baby.
Using this medicine while breastfeeding might not be safe. Ask your doctor about any possible problems.
Older adults might feel the effects of this medicine more, so be careful if you are older.
How to use cyclobenzaprine
Cyclobenzaprine comes in two forms: a tablet and a slow-release capsule, which you take by mouth.
The tablet is usually taken with or without food three times a day, while the slow-release capsule is taken with or without food once a day. Do not use this medicine for more than three weeks without talking to your doctor.
Make sure to:
- Read and follow the instructions on your prescription label carefully.
- If there is anything you do not understand, ask your doctor or pharmacist to explain it.
- Take cyclobenzaprine just as your doctor tells you to. Do not take more or less, or take it more often than you should.
If you have trouble swallowing the slow-release capsule:
- Do not chew or crush it.
- Instead, you can open the capsule and mix the inside with applesauce.
- Eat this mixture right away and swallow it without chewing.
After you have taken it, have a drink and make sure to swish and swallow to get all the medicine.
Cyclobenzaprine side effects
Cyclobenzaprine can make you feel very tired and dizzy, especially in the few hours after taking it. It can also cause some other problems.
Here are the usual side effects:
- Your mouth might get dry.
- You might feel dizzy or tired.
- You could have trouble going to the bathroom (constipation).
- You might feel very sleepy.
- You could feel like throwing up (nausea).
- Your stomach might hurt like heartburn.
If these issues are not too bad, they might get better in a few days or a couple of weeks. However, if they are really bothering you or do not go away, talk to your doctor or pharmacist.
Serious side effects
If you have really bad side effects, call your doctor right away. If your symptoms are very serious or feel like a big emergency, call 911. Serious side effects can show up like this:
Heart problems – You might:
- Pass out
- Feel your heart beating too fast or in a strange way
- Get confused
- Have trouble talking or understanding things
- Lose control or feel numb in your face, arms, or legs
- Have trouble seeing with one or both of your eyes
Serotonin syndrome – This can make you feel:
- Very agitated or restless
- Like you are seeing or hearing things that are not there
- Have seizures (your body shakes suddenly)
- Feel like throwing up (nausea)
