"I want to give my 86 y.o. mother some topical cream for arthritis. She is on a blood thinner (warfarin) and BP medications, and is generally very sensitive to medications. I understand topical creams (as opposed to transdermal patches) do not enter the blood stream, but I can’t seem to find definitive info on whether they are safe for elderly people on other meds. I’m hoping someone with a medical background can reply. Thx."
I’d consider topical cannabis preparations like creams or lotions safe for your 86 year old mother. The information you have found regarding cannabis not entering the general circulation when it is applied to the skin is correct. I would anticipate no interaction with her medications when used in this manner. Patients have reported subjective benefit from topical cannabis preparations, and as long as the skin is intact I would give these a try without worrying about unwanted effects.
I agree with Dr. Elkind. With heavy usage, cannabis can alter how quickly the liver metabolizes certain medications such as warfarin. However with topicals, only negligible amounts of cannabinoids are absorbed into the circulation. I always recommend topical products with a healthy amount of THC such as
Many patients report topical cannabis to be effective at relieve the symptoms of arthritis. Your grandmother is on warfarin which is a blood thinner and marijuana also acts as a blood thinner so she is not a great candidate for ingestion or inhalation however since our skin has a low absorption rate for cannabis, it would be safe. You are right that most topicals will not break the blood stream barrier. Generally they only to penetrate to the receptors in the area applied. I agree with Dr. Elkind and Dr. Kim and think that she should definitely give it a try.