For chronic pain management, which TENS frequency is commonly used?

• A. 1–5 Hz
• B. 2–10 Hz
• C. 40–60 Hz
• D. 50–100 Hz

Answer: (B)

Low-frequency TENS, in the range of about 2–10 Hz, is commonly used for chronic pain because it engages the body's endogenous pain control systems. When stimulated at these low frequencies, the nervous system releases endorphins and enkephalins in the spinal cord and brain, producing analgesia that often lasts well beyond the stimulation period. This longer-lasting relief is particularly helpful for chronic pain management, where sustained control is the goal.

In contrast, higher-frequency TENS (roughly 40–60 Hz or 50–100 Hz) tends to provide quicker, more immediate relief by activating different sensory pathways, but the analgesic effects typically fade soon after the treatment ends and may require more frequent sessions. So, the 2–10 Hz range best fits the goal of durable pain control in chronic conditions.