I thoroughly researched Penetrex before I bought it and believe me it lived up to the multitude of 5 star ratings it received. Suffering from a sudden and severe onset of RA (precipitated by an adverse reaction to the second dose of Shingrix), exacerbation of my preexisting osteoarthritis, and suffering level 15 pain from acute myalgia, neuropathy and polyarthralgia for the past two years I was desperate for some lasting pain relief. The only pain medication I take is an OTC NSAID. Penetrex has relieved almost all of the joint, muscle, tendon pain that has kept me from having a full night's sleep for the past two years. Now I know it will not work for everyone, but it worked for me, and I believe it is worthwhile for anyone who is suffering joint, muscle or tendon pain should give it a try by purchasing a 2oz jar...if it works, buy more like I did...if it doesn't work for you, your monetary loss is little and you can look for something else. I am so grateful for this product and what it has done for me; it has helped with my pain so much I can enjoy life and getting out and about more.