20 Astonishing Reasons Why Your Muscle Relaxers Might Not Be Your Friend

Dizziness is a common side effect of centrally-acting skeletal muscle relaxants. These medications are prescribed alongside physical therapy and rest to help with muscle spasm relief. They act on the central nervous system by creating a sedating effect or preventing the nerves from transmitting pain signals to the brain. As the effects of long-term use are not proven, patients should not take these for longer than two to three weeks. Patients experiencing dizziness may have trouble keeping their balance and suddenly get lightheaded when they stand up. Though dizziness is not always a sign of a serious problem, patients should talk to a doctor if it is interfering with their day-to-day life. They also should not drive a car or do other potentially dangerous tasks until they are aware of how the medication affects them. Individuals should not take muscle relaxants with alcohol or other central nervous system depressants, as this can lead to worse dizziness and potential coma or death.

2. Fatigue Or Drowsiness

Fatigue and drowsiness are also common side effects of a muscle relaxer that works on the central nervous system. This is another reason individuals should not drive or do potentially dangerous activities until they know how they affect them. Some patients may find muscle relaxers make them fall asleep much more quickly than trying to sleep without these medications. Of course, individuals should not take these medications with alcohol. The reason is that if they do, the fatigue they cause can be just the start of a potentially life-threatening reaction. If patients find the fatigue they are experiencing is interfering with their daily life, they should talk to a doctor about alternative options for treatment. It is important not to combine muscle relaxers with sleeping medications or depressant drugs like opioids. Individuals also should not use them with St. John's wort or similar herbal supplements. Patients who have liver problems, who have a neurological disorder or mental health issue, or who are older than sixty-five years old, should talk to their doctor about how to safely mitigate the effects of muscle relaxers.

3. Depression

Any muscle relaxant individuals take will have some side effects, especially if it acts on the central nervous system. Depression is a common side effect of muscle relaxers. The symptoms will typically go away once patients stop taking the relaxer or lower their dose. Many muscle relaxers work by inhibiting the central nervous system function. This helps relieve the pain from muscle spasms and spasticity by keeping individuals from feeling it as fully. However, it can also cause their emotions to feel blunted and thoughts to feel sluggish and slow. Clinical depression occurs when individuals feel intensely sad or empty in ways that interfere in day-to-day life. These feelings must continue for at least two weeks for patients to receive an official diagnosis of major depression. Many patients with clinical depression feel worthless, helpless, and hopeless. They may lose interest in their plans for the future, stop connecting with their friends and family, and struggle to enjoy activities that previously brought them pleasure. If someone is feeling depressed, they should talk to a doctor.

4. Reduced Blood Pressure

Depending on the drug and the way it works within the body, individuals may experience reduced blood pressure due to muscle relaxants. This is not always a bad thing, especially if patients have slightly elevated blood pressure. However, if they already take medication to lower their blood pressure, it may interact with the relaxant and cause their blood pressure to become too low. Low blood pressure is defined as any reading lower than 90/60, but the ideal blood pressure is 120/80. When blood pressure is low on a long-term basis, it is usually not a cause for concern, as naturally low blood pressure does not tend to cause symptoms. However, when an individual's blood pressure drops suddenly, it can cause their brain to be deprived of oxygen because it is not getting adequate blood supply. A sudden blood pressure drop happens most often when individuals get up from a seated position or sit up after laying down. When this happens, individuals might suddenly feel dizzy and faint. Some also experience low blood pressure if they stand for long periods.

5. Muscle Weakness

Muscle weakness is a common side effect of muscle relaxers. In most cases, this is not a cause for concern. Different muscle relaxers may cause various levels of potential weakness. As they ease muscle spasms or muscle spasticity, they may make it difficult for the muscle to contract fully. This leads the muscle to be unable to support the same weight it usually can, otherwise known as muscle weakness. Mild muscle weakness is an expected part of muscle relaxers. However, if the muscle weakness is serious enough to impair a patient's mobility or day-to-day activities, they should talk to their doctor. Patients should also talk to their doctor if they feel like the weakness is accompanied by other muscle symptoms like pain and fatigue. Some muscle weakness is expected, especially when treating muscle spasticity. The drugs must reduce the muscle's ability to contract in order to reduce spasticity.

6. Dry Mouth

Dry mouth means that the salivary glands in an individual’s mouth do not produce sufficient amounts of saliva to keep their mouth sufficiently lubricated. Thus, affected individuals feel as if their mouth is dry. Dry mouth can be temporary, though patients may see significant complications if it does not disappear quickly. This is because saliva protects the teeth from tooth decay by reducing the growth of bacteria and neutralizing the acids they produce. Saliva also makes it easier to chew and swallow food. One of the most common triggers for dry mouth is medications, including muscle relaxers. If this happens, doctors have a couple of options. One of them is to adjust the dose of the patient’s muscle relaxant. They may also change the patient to a different medication or prescribe medication to induce saliva production.

7. Constipation

Unfortunately, muscle relaxers are one of the many types of medications that have constipation as a side effect. Constipation, of course, occurs when individuals have three or fewer bowel movements a week. In many instances, individuals dealing with constipation also strain when they are trying to have a bowel movement. Additional signs of constipation include hard stools, lumpy stools, and the feeling of not completely emptying the bowels. Some muscle relaxers have anticholinergic effects, which experts believe is why constipation is a potential side effect. Individuals dealing with this side effect may need to adjust their dose or switch to a different muscle relaxant.

8. Nausea

Nausea is widely considered to be the most common side effect. Of course, this means that it is a common side effect of muscle relaxers. Many patients will only experience mild nausea due to their muscle relaxer. In addition, nausea from this type of medication can subside as patients adjust to it. However, persistent nausea may require changes. Patients may have to have their muscle relaxant dose adjusted or switch to an alternative that does not trigger this side effect. Another option is to employ natural remedies for nausea, including drinking ginger tea.

9. Heartburn

Heartburn is a burning pain that occurs in an individual’s chest. Typically, affected individuals will feel heartburn behind their breastbone. Heartburn often worsens when individuals bend over or are lying down, as well as in the evening or after eating a meal. In rare cases, patients taking muscle relaxers will experience heartburn as a side effect. Thankfully, the pain is usually mild and easily managed. Patients can have their dose adjusted or switch to a new medication. Lifestyle remedies can also assist with managing heartburn. However, if individuals want to try over-the-counter medications for heartburn, they should discuss it with their doctor first to avoid a potential interaction with their muscle relaxer.

10. Heart Palpitations

Heart palpitations refer to the feeling of a fast-beating heart. Many individuals describe it as a fluttering or pounding feeling in their heart. Heart palpitations, when they are the result of exercise or stress, are often temporary. However, they are a dangerous side effect of some medications, including muscle relaxers. Patients who take muscle relaxers and experience heart palpitations should call their doctor immediately. In quite a few cases, patients will need emergency medical care. Severe heart palpitations can indicate that patients have taken too many muscle relaxers. Many patients must stop taking their muscle relaxer immediately. The emergency room can treat them, though they should also consult their doctor for additional treatment, including if they still need medication for an underlying condition or medical issue.

11. Urinary Retention: The Bladder's Reluctance

An often-overlooked side effect of muscle relaxers, particularly those with strong anticholinergic properties, is urinary retention – difficulty emptying the bladder completely. This isn't just about needing to go; it can lead to discomfort, bladder distension, and an increased risk of urinary tract infections. The medication's effect on smooth muscle relaxation extends to the bladder, inhibiting its ability to contract effectively. Recognizing this nuanced effect on bladder function is crucial for preventing urinary complications, especially in older adults or those with prostate issues.

12. Cognitive Impairment ("Brain Fog"): The Mental Muddle

Beyond simple drowsiness, muscle relaxers can induce significant cognitive impairment, often described as "brain fog." This is an insidious side effect where patients experience difficulty concentrating, memory problems, slowed thinking, and impaired judgment. This profound impact on cognitive function extends far beyond pain relief, affecting daily tasks, work performance, and overall quality of life. Understanding that the medication actively blunts mental sharpness, rather than just making you tired, is key to managing its use and avoiding unintended mental blunting.

13. Increased Fall Risk (Beyond Dizziness): Motor Control Compromise

Muscle relaxers notoriously increase fall risk, but it's more complex than just dizziness. They compromise motor control by broadly relaxing muscles and affecting balance centers in the brain. This can lead to unsteady gait, reduced coordination, and slowed reaction time. This isn't just for the elderly; anyone taking these medications is at an elevated risk of accidents. Recognizing this comprehensive impairment of balance and motor skills, rather than just a feeling of lightheadedness, is vital for proactive safety measures to prevent injury.

14. Drug-Drug Interactions (Synergistic Depression): The Hidden Combinations

A critical, often unseen, danger of muscle relaxers lies in their profound drug-drug interactions, particularly with other central nervous system depressants. Combining them with opioids, benzodiazepines (e.g., Xanax, Valium), alcohol, or even certain antihistamines can create a dangerous synergistic effect, leading to severe respiratory depression, extreme sedation, coma, or even death. The insidious part is unawareness of these potent combinations. Always disclose all medications and supplements to your doctor and pharmacist to avoid these potentially fatal interactions.

15. Dependence & Withdrawal: The Body's Adaptation

While typically prescribed for short-term use, prolonged muscle relaxer use can lead to physical dependence, even in non-addicted individuals. This means the body adapts to the drug's presence, and abrupt discontinuation can trigger unpleasant withdrawal symptoms like rebound muscle spasms, anxiety, insomnia, tremors, or seizures. This insidious dependence highlights why careful tapering under medical supervision is crucial when discontinuing the medication, preventing a potentially severe physiological backlash.

16. Paradoxical Muscle Spasms (Rare): The Unintended Consequence

In rare and startling cases, muscle relaxers can paradoxically worsen or induce muscle spasms. This unexpected reaction, though uncommon, highlights the complex and sometimes unpredictable nature of these medications' central nervous system effects. Instead of calming the muscles, the drug can trigger an abnormal neurological response leading to increased muscle rigidity or spasticity. Recognizing this extremely rare, counterintuitive side effect is important, as it immediately signals that the medication is not only unhelpful but actively detrimental, requiring immediate cessation and medical review.

17. Liver Toxicity (Hepatotoxicity): The Silent Organ Strain

Certain muscle relaxers, like Tizanidine or Baclofen (especially at higher doses or with prolonged use), can surprisingly cause liver toxicity. This insidious damage is often silent in its early stages, with symptoms only appearing once significant liver compromise has occurred. Regular liver function tests are crucial for patients on long-term therapy to monitor for elevated liver enzymes, which signal stress or damage to the organ. Understanding this potential for hepatotoxicity underscores the need for careful medical oversight and periodic blood work.

18. Exacerbation of Glaucoma: The Ocular Pressure Threat

For individuals with certain types of glaucoma (specifically narrow-angle glaucoma), muscle relaxers with anticholinergic properties can pose a serious, hidden threat. These medications can cause dilation of the pupils, which can narrow the drainage angle in the eye, potentially leading to a sudden, dangerous increase in intraocular pressure. This acute glaucoma attack can cause severe eye pain, blurred vision, and permanent vision loss if not immediately treated. Always disclose a history of glaucoma to your doctor before starting a muscle relaxer.

19. Impaired Driving Performance (Beyond Drowsiness): Complex Coordination Loss

The risk of impaired driving performance from muscle relaxers extends beyond simple drowsiness. These medications interfere with complex cognitive and motor functions crucial for safe driving: reaction time, judgment, coordination, spatial awareness, and visual processing. This insidious impairment can make driving as dangerous as driving under the influence of alcohol, even if the user doesn't feel overtly sleepy. Understanding this comprehensive neurological compromise is vital, as it applies to operating any heavy machinery or performing tasks requiring fine motor control.

20. Rebound Insomnia: The Nightly Aftershock

Ironically, while muscle relaxers can induce drowsiness, their discontinuation, especially after prolonged use, can lead to rebound insomnia. This startling effect occurs as the brain, adapted to the drug's sedative influence, struggles to re-regulate its natural sleep-wake cycles. Patients may experience severe difficulty falling or staying asleep, even worse than their original sleep issues. This highlights a subtle but significant post-treatment challenge, underscoring the importance of gradual tapering under medical guidance to mitigate this uncomfortable aftershock.

Beyond Relief: Understanding the Full Scope of Muscle Relaxers

Muscle relaxers, while powerful allies in pain relief, are complex pharmaceuticals whose impact extends far beyond easing a spasm. As these 20 astonishing reasons reveal, their mechanisms of action, side effects, and interactions weave an intricate web of potential consequences – from subtle cognitive shifts and vital organ strain to hidden cardiovascular risks and the insidious challenges of dependence. Understanding these unseen signals isn't about fear; it's about empowerment. Armed with this knowledge, you can engage in informed discussions with your healthcare provider, make conscious choices, and navigate your treatment path with vigilance, ensuring that your pursuit of comfort doesn't inadvertently lead to unforeseen complications. Your well-being depends on seeing the full picture.