Which analgesic alternative may be used if first-line analgesic is contraindicated or unavailable?

• A. Ketamine
• B. Morphine
• C. Fentanyl
• D. Acetaminophen

Answer: (A)

When the usual first-line analgesic cannot be used or isn’t available, an option that provides effective pain relief without relying on opioids is ketamine. Ketamine works as an NMDA receptor antagonist, giving strong analgesia at subanesthetic doses and, importantly in austere settings, it preserves airway reflexes and spontaneous breathing. It can be given IV or IM, so it’s practical even when IV access is limited, and it tends to support blood pressure rather than cause the pronounced respiratory depression that opioids can. This combination of reliable analgesia, minimal impact on respiration, and suitability for unstable or trauma patients makes it a preferred alternative when first-line analgesics are contraindicated or unavailable. Opioids like morphine or fentanyl are effective but carry higher risks of respiratory depression and hemodynamic effects in certain patients, while acetaminophen is typically a first-line option; if it’s not usable, ketamine fills that gap with a favorable safety profile in field conditions.