Identifying the Orange Pill with N 500 Imprint
The orange, round pill with the imprint 'N 500' on one side and a break line is Chlorzoxazone, manufactured by Aurobindo Pharma USA Inc.. This prescription-only medication is approximately 13mm in size. Identifying pills by their color, shape, and imprint is a crucial part of pharmacology. While some pills may appear similar, this specific combination identifies this particular drug.
The Function and Mechanism of Chlorzoxazone
Chlorzoxazone is a centrally acting skeletal muscle relaxant used to treat acute, painful musculoskeletal conditions alongside rest and physical therapy. It works in the central nervous system, specifically the spinal cord and subcortical areas of the brain, to inhibit multisynaptic reflex arcs responsible for muscle spasms. This action leads to muscle relaxation, pain relief, and improved mobility. Unlike some other muscle relaxants, it primarily affects the CNS rather than directly acting on the muscles.
Administration Guidelines
Chlorzoxazone is typically taken orally. The specific amount and frequency of administration will be determined by a healthcare professional based on the individual's condition and response to treatment. It is crucial to follow the prescribed instructions precisely. Chlorzoxazone is generally not recommended for children, and dosage in all patients should be adjusted as symptoms improve. Always take this medication exactly as prescribed by your doctor.
Common Side Effects and Serious Warnings
Chlorzoxazone can cause side effects. Common ones include drowsiness, dizziness, lightheadedness, fatigue, upset stomach, and headache. It can also cause harmless, temporary orange or reddish-purple urine discoloration.
Seek immediate medical attention if you experience symptoms of serious liver problems such as fever, rash, loss of appetite, nausea, abdominal pain, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes).
Comparison of Common Muscle Relaxants
| Feature | Chlorzoxazone (N 500) | Cyclobenzaprine (Flexeril) | Methocarbamol (Robaxin) |
|---|---|---|---|
| Mechanism | Acts primarily on the CNS at the spinal cord and subcortical areas to inhibit reflex arcs. | Works in the brainstem to relieve muscle spasms. | Less sedating and fewer drug interactions than some other muscle relaxers. |
| Common Uses | Acute, painful musculoskeletal conditions and muscle spasms. | Acute muscle discomfort, can be used for fibromyalgia. | Muscle spasms and pain associated with musculoskeletal conditions. |
| Administration | Taken orally, frequency determined by physician. | Immediate-release (IR) multiple times daily or Extended-release (ER) once daily, as prescribed. | Amount and frequency vary, as prescribed. |
| Key Risks | Rare, but potentially fatal, liver toxicity; caution with alcohol/CNS depressants. | Dry mouth, potential for serotonin syndrome with certain medications. | Generally well-tolerated, but can cause sedation; caution with CNS depressants. |
Precautions, Interactions, and Warnings
Use Chlorzoxazone cautiously. Avoid alcohol and other CNS depressants like antihistamines, sedatives, or opioid pain relievers, as they can increase drowsiness. Due to potential dizziness and drowsiness, avoid driving or operating heavy machinery until you know how the medication affects you.
Although rare, serious and sometimes fatal liver toxicity has been reported; the exact cause is unclear. Monitor for symptoms of liver problems. Do not use this medication if you are allergic to it. For more information on interactions and warnings, consult reliable drug databases.
Conclusion
The orange, round pill marked 'N 500' is Chlorzoxazone, a prescription muscle relaxant for painful musculoskeletal conditions. It acts on the central nervous system to relieve muscle spasms but carries risks of side effects, including rare but severe liver toxicity, and increased sedation when combined with alcohol or other CNS depressants. Always follow your doctor's instructions, be aware of potential side effects, and be cautious with activities requiring alertness. Consult a healthcare professional for accurate drug identification and medical advice. For more information, refer to trusted sources like Drugs.com.
