Creams, ointments, gels, sprays, lotions and patches are medicines that will enter your body by penetrating through the skin and entering the bloodstream. They can cause side effects if you use too much of the medicine.
Several years ago, two young college students in different states died after they applied a numbing gel to their legs to prepare for a laser hair removal procedure. The gel contained high doses of two numbing medicines called lidocaine and tetracaine. The gel was intended to help ease any pain associated with the procedure. One of the students was given the gel by staff at the spa where she was planning to have the procedure, and the other woman picked up the gel from the pharmacy. Employees at the hair removal spas told the women to apply the gel to their legs before the procedure and to cover their legs in plastic wrap. Both women had a fatal reaction to the gel because too much medicine entered their bodies through the skin. One woman had a seizure in her car on the way to her appointment. She lapsed into a coma and died the next week. The other woman had a seizure and was on a ventilator (breathing machine) for 2 years before she died.
These deadly reactions were caused by high doses of the numbing medicines in the gel and applying the gel to very large areas of skin (from groin to ankle). Also, using plastic wrap over the skin heated it, which caused nearby blood vessels to dilate and blood flow to increase. That, in turn, allowed more medicine than usual to be absorbed and circulated, which eventually was toxic to the body. There are many other medicines that are applied to skin, like antibiotics, cortisone-like drugs and antifungals. All of these can be absorbed, sometimes leading to side effects.
These cases above involved prescribed medicines, but harm has also resulted from using too much over-the-counter (OTC) medicines applied to the skin. For example, the death of a 17-year-old girl was blamed on the use of too much cream for muscle aches. She was a cross country runner and had been using the cream all over her legs to soothe aching muscles after exercise. Heat and exercise can increase the amount of medicine entering your body. Her body apparently absorbed high levels of methyl salicylate, an anti-inflammatory medicine related to aspirin that is found in sports creams such as Bengay and Icy Hot. Used correctly, these creams can provide temporary relief from muscle pain but they shouldn’t be used for more than a week. Using too much over days or weeks is more dangerous than one-time use of a large amount of the cream.
The cases are all examples of harm that can occur when applying too much medicine on the skin. Even though harm does not happen often, medicines in creams, ointments, gels, sprays, and patches can enter your body just like medicines taken by mouth. When using these medicines, be sure to follow directions and heed any warnings found on the drug facts label on all OTC drug items.
Here are some tips to avoid problems when using these medications:
1) Use the medicine exactly as stated on the label, or exactly as your doctor told you. Do not use more of the medicine than prescribed, and do not use it more often or longer than recommended.
2) Apply creams, ointments, gels, and sprays sparingly and only on the areas needed, not all over your body.
3) Apply sparingly to areas of your skin that rub together, like under the breasts or between the buttocks. When skin is rubbed together, more medicine can be absorbed.
4) Avoid applying creams, ointments, gels, sprays and medication patches to broken skin.
5) Do not use heat or tight bandages or other coverings, like plastic wrap, for any of these products, unless told to do so by your doctor. Remember that tight bandages make the skin warmer, and heat increases the amount of medicine absorbed into the body. Do not apply heat (e.g., prolonged sunlight, hot tubs, heating pad, tanning beds) without checking with your doctor.
6) Since some cosmetic procedures may be performed without a medical doctor present (e.g., laser hair removal), consider having a pharmacist or doctor first review any creams or ointments you are instructed to apply to the skin. Talk to a pharmacist when buying prescription and OTC creams, ointments, sprays, gels, and patches so you use the products safely, know what side effects are possible and what to do about them if they happen.