Therapik® is a small, portable, hand-held, battery-powered device. It measures approximately 3cm x 3cm x 10cm and weighs less than four ounces, including the battery. The heat is initiated by use of a simple, non-locking, finger or thumb activated on/off switch. Heat is produced as long as the switch is depressed; when pressure on the switch is released, the circuit is interrupted and heat is no longer produced.
The source of the infrared heat is a small electric bulb with a nominal voltage rating of 5 volts. The bulb is driven by a user replaceable 9-volt alkaline battery, which effectively overdrives the bulb to produce an energy output of approximately 1.25 watts. This overdrive effect produces the desired heat output. The bulb is recessed approximately 2mm inside the ABS housing of the Therapik®; the light orifice is covered with a metal mesh that is in turn also slightly recessed to prevent direct contact with the skin. The mesh also avoids pushing a stinger further into the skin in the event that the stinger has been left behind in the wound. Thus, treatment may be initiated to inactivate the venom before attempting to remove the stinger.
The bulb is approximately 3mm in diameter, resulting in a nominal cross-sectional area of about 7mm². The output of the 1.25 watt bulb, therefore, provides a total power density of approximately 0.18W/mm². The light orifice is a circle with a nominal area of 28mm² located approximately 2mm from the closest point of the bulb. The metallic mesh material effectively blocks a percentage of the orifice. When corrected to account for the distance between the bulb and the light orifice and the blockage of a percentage of the orifice by the mesh material, the actual heat flux density produced by the device is approximately 0.03 W/mm².
The application of this power density to the skin using the Therapik® results in the delivery of heat to a depth of approximately 2mm. The user is instructed to apply the device for as long as the heat is bearable on the skin (approximately 20 – 30 seconds).
This effectively raises the temperature of the tissue up to 2mm beneath the skin to 50°C - 60°C, which is the temperature, required to destroy the effect of thermolabile venoms. Because the heat becomes uncomfortable well before a burn occurs, it is virtually impossible to injure the skin through normal use of the Therapik®.
The user is instructed to replace the 9-volt battery at least once a year or sooner if used frequently, a adepleted battery requires a longer time to heat up. Recommended is an Alkaline battery, but if not available use preferably a Rechargeable 9V Battery.