Consultant Physician, Shreeja Clinic, Dombivali, India.
AIM: Now a day, multimodal analgesia is commonly used for pain management in elderly patients, but it also increases the risk of adverse drug reactions.CASE PRESENTATION: A 72-year-old male was initiated on multimodal analgesia including tramadol (37.5mg), thiocolchicoside (4mg), buprenorphine transdermal patch (5 mg), and pregabalin (75 mg). Within a short duration of therapy, the patient developed acute onset lower limb weakness, leading to difficulty in ambulation. There was no history suggestive of stroke, trauma, or prior neuromuscular disease. After suspecting drug-induced etiology, the medications were discontinued. The patient showed gradual and significant improvement in lower limb strength after withdrawal of therapy.DISCUSSION: The use of multimodal analgesia resulted in additive neuromuscular side effects resulting in fall and lower limb weakness, which were transient and reversible. CONCLUSION: This case highlights the risk of neuromuscular adverse effects due to polypharmacy in geriatric patients and emphasizes cautious use of multimodal analgesia..
Effective management of acute severe musculoskeletal pain often necessitates a multimodal pharmacological approach [1, 2]. So, clinicians frequently employ a combination of opioid analgesics, such as tramadol and buprenorphine, pregabalin alongside skeletal muscle relaxants like thiocolchicoside to achieve synergistic pain relief.[2] while these agents are efficacious individually, their concurrent use may impact the motor function and patient safety, especially in elderly people [ age > 60 years]. According to previously published studies, drugs such as hypnotics, antipsychotics, antidepressants, and opioids are associated with an increased risk of causing falls [3, 4].Due to polypharmacy and frailty in the elderly; complications, most notably falls and asthenia (generalized muscle weakness and loss of energy) occur. However, the concomitant administration of these agents leads to profound central nervous system (CNS) depression [5, 6]. Adverse effects such as muscle weakness, motor incoordination, drastically increased risk of falls and generalized asthenia have been documented with each medication independently [4,8]. This case study highlights the risks of using high-potency, multimodal analgesics in elderly patients. While combining medications can improve pain relief, it also increases the risk of severe physical weakness. This case illustrates the critical need for clinicians to balance additive multimodal analgesia with rigorous, real-world monitoring of a patient’s mobility and physical function.
CASE REPORT:
INITIAL PRESENTATION AND INJURY:
A 73-year-old male had sustained blunt force trauma on right side chest, at 06:30 hours on day 1. On day 2, radiographic evaluation via chest x-ray confirmed minor fractures of the 10th, 11th, and 12th ribs on right side. The patient reported significant pain even during minor movements. A multimodal analgesic regimen was then initiated, consisting of a buprenorphine transdermal patch (5 mg), a fixed-dose combination (FDC) of tramadol (37.5 mg) and paracetamol (325 mg) bd, pregaba m 75mg and thiocolchicoside (4 mg) bd.
CLINICAL COURSE AND ADVERSE EVENT:
On day 3, in morning hours, he got up to go to washroom, but could not walk 10-12 steps and experienced profound lower limb weakness and a marked loss of physical strength. Functional impairment was severe; he was unable to walk even with assistance. Physical examination revealed bilateral pedal edema, though the patient denied having dizziness or vertigo.
INTERVENTION AND RECOVERY:
The health care provider was contacted immediately after the incident, and after medical consultation, the tramadol/paracetamol combination, pregabalin and thiocolchicoside were discontinued due to suspected drug-induced neuro-muscular depression. By the end of day 4, the patient’s lower limb weakness showed significant clinical improvement, and he was able to ambulate short distances with minimal assistance.
RECHALLENGE AND FOLLOW-UP:
On day 5, the tramadol and thiocolchicoside therapy was reintroduced to manage persistent rib pain. Pregabalin was introduced a day after. The vitals were stable except for bilateral pedal edema. No other significant complaints were noted.
DISCUSSION
Using multimodal analgesia in older adults for management of acute musculoskeletal pain requires a careful approach including effective pain relief and minimizing the risk of side effects.
In above case, after the fall incident, medications via oral route were stopped, but, transdermal buprenorphine patch was not removed. The rationale of the regime was to control severe pain which was occurring on minor movements and increased with inspiration.
Transdermal patch of buprenorphine: the benefit of transdermal administration, particularly for elderly patients, is a slow increase of plasma concentration without a sudden peak, which results in a smaller number of adverse effects [7] . It is effective and safe for certain types of acute pain in appropriate patients [8, 9]
Tramadol is a relatively safe opioid and has multiple analgesic mechanisms [10]. Its FDC with nonsteroidal anti-inflammatory drugs (NSAIDS) has synergistic pain reliving action with benefit of dose reduction of both drugs [2].
The effects of Thiocolchicoside are symptomatic relief of post-operative pain, chronic pain and pain due to acute musculoskeletal injuries [11] with absence of sedation [12].
Pregabalin is used as adjuvant analgesic, may be to treat insomnia due to acute pain and injury but it has serious adverse effects such as somnolence and dizziness, especially in elderly patients [5].
|
Drug |
Mechanism of Action |
Adverse effect |
|
Buprenorphine transdermal patch 5mg |
Partial agonist on the mu-opioid receptors Kappa opioid receptors |
Spinal and supraspinal analgesia, respiratory depression, sedation,[13] |
|
Tramadol 37.5mg+ PCM 325mg FDC PO |
Centrally acting μ-opioid receptor agonist and SNRI |
Dizziness, sedation, and impaired cognitive function, which could increase the risk of falls[14] |
|
Thiocolchicoside 4mg PO |
[partially known]GABA A receptor + glycine receptor antagonist, |
Epileptogenic[12] |
|
Pregabalin 75mg PO |
Alpha-2-delta subunit of presynaptic voltage-gated calcium channels in CNS |
Somnolence and dizziness Edema[15] |
This clinical sequence suggests a transient, multi-factorial interaction between the potent mu-opioid agonists and the skeletal muscle relaxant in an elderly patient. The common side effects of analgesic medications are dizziness, drowsiness, and hypotension; therefore, a geriatric patient’s risk for falls and fractures can increase when skeletal muscle relaxants are used [3, 6]. Compared with the average adult, geriatric patients are at increased risk for falls because of unsteady gait, loss of coordination or muscle strength, and other age-related declines in mobility and cognition [3]. Because antispastics and antispasmodics work within the central nervous system, their side effects can pose fall risk for geriatric patients. The lower limb weakness is likely result of synergistic central nervous system depression. Concomitant use of these agents leads to an additive risk of sedation, generalized weakness, along with increased frailty due to age. Furthermore, thiocolchicoside caused reduced muscle tone to a degree that manifested as lower limb asthenia [12]. Notably, the patient did not experience a recurrence of lower limb weakness upon rechallenge.
CONCLUSION
This case underscores that for the geriatric population, "successful" pain management must be measured by functional outcomes. The sudden "loss of strength" reported here represents a significant safety failure. We recommend that clinicians should adopt a "start low, go slow"—when initiating high-potency multimodal regimens. Also, more studies on the use of multimodal analgesics in acute injury in elderly patients should be undertaken. Safer alternative drugs or alternative therapy should also be considered, especially in elderly patients.
REFERENCES
Neha Kakirde, A Case Report Study on Acute Lower Limb Weakness Secondary to Multimodal Analgesic Therapy in a Geriatric Patient in Private Clinic in Suburban Mumbai, Int. J. of Pharm. Sci., 2026, Vol 4, Issue 4, 2503-2506, https://doi.org/10.5281/zenodo.19605987
10.5281/zenodo.19605987
