Some infrared light bulbs emit visible red light as well as invisible infrared radiation. Some heat lamps also do this. Some infrared bulbs emit no visible light. But all of these are unsafe to use outside of a medical setting because infrared radiation can damage the eye.
There are many studies showing therapeutic benefits of red light therapy but talk to your physician about these.
Infrared radiation can actually damage the eye. For example, see this scientific study on the harmful effects of infrared scanning devices in smartphones. The study was conducted in 2013, and found that infrared radiation damaged the eyes of rabbits.
*Note: the animal testing in the above experiments is unnecessary. See this article to understand why humanity does not need animal testing in order to advance medically/technologically.
Other studies showing that infrared bio scanning is dangerous are being released. There are also numerous anecdotal reports from people reporting pain in their eyes and headaches after using their smartphones’ infrared scanning mechanism. Infrared scanning in smartphones like Face ID in the iPhone X is not safe.
Other light bulbs to avoid: Compact fluorescent bulbs
CFL’s contain mercury inside the bulb, which emits ultraviolet (UV) radiation. This UV exposure has been linked to skin disorders and skin cancers: https://www.ncbi.nlm.nih.gov/pubmed/22724459
CFL bulbs also generate electromagnetic frequencies harmful to health. Leading EMF expert Dr. Magda Havas explains the health hazards associated with these frequencies in her paper “Health Concerns associated with Energy Efficient Lighting and their Electromagnetic Emissions”: http://www.weepinitiative.org/LINKEDDOCS/scientific/08_Havas_CFL_SCENIHR.pdf
Other light bulbs to avoid: LED (light emitting diode) bulbs
LEDs contain lead, arsenic and a dozen other potentially dangerous substances. They also cause serious eye strain and migraines. Avoid purchasing these. https://www.scientificamerican.com/article/led-lightbulb-concerns/
The safest light bulb: Incandescent Bulbs
The safest and healthiest light bulb is the good old fashioned incandescent light bulb. They are no longer sold in many stores so you may have to purchase online. These bulbs contain far less toxins than the newer bulbs and they emit a gentle, non-glaring warm spectrum of light that does not cause migraines or eye strain.
There need not be environmental concerns about the energy required to operate incandescent bulbs because incandescent light bulbs use up a minute fraction of electricity when compared to other devices in domestic or industrial settings. Also, soon all domiciles will have their own solar panesl and battery systems- we will have true energy independence and incandescent bulbs will be a part of that healthy, green future.
p.s Here is some info on how to protect yourself from harmful electromagnetic radiation.