The major advantage of infrared heat lamp is

• A. It emits radiation only ultraviolet rays
• B. It filters out harmful ultraviolet radiation
• C. Local metabolism is increased
• D. Erythemia is produced

Answer: (C)

Raising tissue temperature to boost local metabolism is the main benefit of infrared heat lamps. When the area is warmed, metabolic processes accelerate, speeding enzymatic reactions and tissue repair. This warmth also causes vasodilation, increasing blood flow, oxygen delivery, and nutrient transport while helping remove waste products, all of which support healing. The other statements aren’t the primary advantage: infrared lamps don’t emit only ultraviolet rays, and although some devices may filter UV, that isn’t the key therapeutic benefit. Erythema can occur with heat exposure, but it’s a possible response rather than the desired therapeutic effect.