Subjects who purchased the Allay Lamp are asked to document the effects of spending time in the narrow band of green light it emits, on their headache or any of its associated symptoms.

The Allay Lamp is a consumer product currently available and widely used in the US. It emits low intensity (1-10 lux) narrow band (20 nm) green light (peak wavelength 520 nm) that is marketed as non-irritating to users. In that context, it is not a medical device and does not require a 510(k).

Number of days with headache per week without and with using the Allay lamp

Number of days with headache per month without and with using the Allay lamp

Assessing frequency of photophobia during days with headache as depicted by participants using the following options: (1)never, rarely, (2)less than half, (3)half or more, (4)nearly all the time.

Assessing headache severity while using the Allay lamp. Improvement is determined by the number of times participants answer Yes or NO in their daily diary.