Welcome to this month’s Rx Rundown, a recurring series of articles designed to help claims professionals better understand medications commonly prescribed in workers’ compensation claims. Periodically, we spotlight a different medication or therapeutic class, breaking down what it is, why it’s prescribed, potential concerns, and its place in workers’ compensation treatment. Our goal is to provide you with clear, concise information that you can apply in your daily work, helping you make more informed decisions and communicate more effectively with healthcare providers and recovering employees alike. Let’s dive into this month’s feature.
Skeletal Muscle Relaxants:
Skeletal muscle relaxants rank among the most frequently prescribed medications in workers’ compensation claims, particularly for back injuries, strains, and sprains.
Common Workplace Injuries That Trigger Prescriptions for Muscle Relaxants
- Acute low back strain
- Neck injuries
- Repetitive motion injuries
- Lifting-related muscle tears
- Post-surgical muscle spasms
Types of Skeletal Muscle Relaxants:
There are two main categories of skeletal muscle relaxants: antispasmodic and antispastic. Antispastic drugs act on skeletal muscles and the spinal cord, while antispasmodics act on the central nervous system. Antispasmodic skeletal muscle relaxants are more frequently prescribed for back and neck pain compared to antispastics.
Common Antispasmodic skeletal muscle relaxants:
- Carisoprodol (Soma®, Vanadom®)
- Chlorzoxazone (Lorzone®, Parafon Forte DSC®, Relax-DS®, Remular S®)
- Cyclobenzaprine (Fexmid®, Flexeril®, Amrix®)
- Metaxalone (Metaxall®, Skelaxin®)
- Methocarbamol (Robaxin®)
- Orphenadrine (Norflex®)
Common Antispastic skeletal muscle relaxants:
- Baclofen (Lioresal®)
- Dantrolene (Dantrium®)
Dual antispastic/antispasmodic effects:
- Tizanidine (Zanaflex®)
- Diazepam (Valium®)
Workers’ Comp Claim Impact
Return-to-Work Considerations
Muscle relaxants can impact return-to-work timelines for injured workers. Most of these medications cause drowsiness that can delay an employee’s ability to resume normal duties. This is particularly problematic for safety-sensitive positions where operating machinery or driving is required. Employers often need to implement temporary job modifications or restrictions while workers are taking these medications. Additionally, these drugs are frequently flagged in post-injury drug testing, which can create confusion about compliance with company drug policies and require additional documentation from prescribing physicians.
Cost Factors
The financial impact of muscle relaxants extends beyond the direct prescription costs. Generic options like cyclobenzaprine and methocarbamol are widely available. However, brand-name versions can cost 5-10 times more without providing additional clinical benefit. Physician-dispensed muscle relaxants present another cost concern, as they often come with significant markups compared to retail pharmacy prices. Perhaps most significant are the indirect costs associated with extended disability duration when medication side effects prevent timely return to work, which can add thousands of dollars to claim costs.
Red Flags for Claims Professionals
Claims professionals should be alert to several warning signs when reviewing muscle relaxant usage. Prescriptions lasting beyond 2-3 weeks should trigger additional review, as the clinical benefit typically diminishes after this timeframe.
According to the Official Disability Guidelines, muscle relaxants with fewer sedating properties may be considered as a second-line treatment option, but only for short periods (two weeks or less) when treating acute low back pain or flare-ups of chronic back conditions.
The simultaneous prescription of multiple muscle relaxants raises concerns about appropriate medication management and potential overmedication. Combination therapy with opioids without documented medical necessity represents another red flag, as this combination significantly increases sedation risks. Continued use despite lack of documented functional improvement suggests the treatment approach may need reevaluation. Finally, frequent early refill requests may indicate potential misuse or the development of tolerance, particularly with medications like carisoprodol.
Effectiveness for Workplace Injuries
The clinical value of muscle relaxants for workplace injuries follows a predictable timeline, with diminishing returns as treatment extends. These medications demonstrate their greatest effectiveness during the first 7-10 days following an acute injury, when muscle spasm and guarding are most pronounced. Beyond the two-week mark, research indicates minimal continued benefit, with several comparative studies suggesting they often provide no additional pain relief or functional improvement compared to NSAIDs alone for common workplace back injuries. This limited window of effectiveness underscores the importance of using muscle relaxants strategically rather than as long-term solutions, and as part of a comprehensive treatment plan focused on functional restoration and return to work.