What is Norgesic (orphenadrine citrate, aspirin, and caffeine) and what is its controlled substance classification?

Norgesic Medication and Its Controlled Substance Classification

Norgesic is a combination medication containing orphenadrine citrate, aspirin, and caffeine that is not classified as a controlled substance under the DEA scheduling system.

Composition and Mechanism of Action

• Norgesic contains orphenadrine citrate (a centrally acting skeletal muscle relaxant), aspirin (a non-steroidal anti-inflammatory drug), and caffeine 1, 2
• Orphenadrine is similar in structure to diphenhydramine and acts as a centrally acting skeletal muscle relaxant with anticholinergic properties 1
• The precise mechanism of action of orphenadrine is unclear but appears to include anticholinergic effects 1
• Aspirin in Norgesic provides anti-inflammatory effects by inhibiting prostaglandin synthesis 2, 3
• Caffeine serves as an adjunctive therapy that provides synergistic analgesia when combined with other medications 4

Clinical Uses

• Norgesic is primarily used for the relief of pain associated with musculoskeletal conditions, particularly tension of the cervical and upper thoracic musculature 5
• The combination has shown efficacy in providing pain relief from myalgia nuchae (neck muscle pain) 5
• Norgesic may be used in the management of acute pain following surgical procedures 6

Controlled Substance Status

• Orphenadrine citrate, the muscle relaxant component in Norgesic, is not classified as a controlled substance under the DEA scheduling system 1
• Unlike other muscle relaxants that may have controlled substance status, Norgesic does not carry restrictions related to prescribing, dispensing, or refilling that are associated with controlled substances 1

Administration Considerations

• The consensus recommendation for orphenadrine-containing medications like Norgesic is to hold on the day of surgical procedures due to potential anticholinergic effects 1
• The medication is commonly administered both preoperatively and perioperatively, except on the day of surgery 1
• Typical dosing of Norgesic is one tablet three times daily 5

Adverse Effects and Precautions

• Adverse effects of orphenadrine include anticholinergic symptoms such as confusion, anxiety, tremors, urinary retention, dry mouth, constipation, and cardiovascular instability 1
• Norgesic should be used with caution in patients with tachycardia, cardiac decompensation, coronary insufficiency, and cardiac arrhythmias, as well as in elderly patients 1
• The aspirin component carries risks of gastrointestinal toxicity, including upper GI bleeding 1, 7
• Norgesic is contraindicated in patients with gastrointestinal tract obstruction, stenosing peptic ulcer disease, prostatic hypertrophy or bladder outlet obstruction, glaucoma, and myasthenia gravis due to the orphenadrine component 1

Drug Interactions

• Orphenadrine potentiates anticholinergic effects when used with other medications that also have anticholinergic properties 1
• The aspirin component may interact with anticoagulants, increasing bleeding risk 3
• Caution should be exercised when combining Norgesic with other central nervous system depressants due to potential additive effects 1

Comparison to Other Analgesics

• Studies have shown that the aspirin in Norgesic provides an anti-inflammatory amount of salicylic acid equivalent to that of plain aspirin 2
• The combination of orphenadrine and acetaminophen (a similar formulation to Norgesic) has demonstrated better analgesic efficacy than either component alone or placebo in post-surgical pain 6
• Unlike opioid analgesics, Norgesic does not carry risks of dependency or controlled substance regulations 1