I don't think the salicylate content is safe for pregnancy though.. Tigerbalm ones is probably safer without salicylate.
i avoid using them too. alternatively i use hot water bag and microwaveable heating herbal bag or rice bag..
I asked my tcm before. And she say is really dependant on the ingredient inside. It's best not to use it.
I asked my gynae before when I had bad backaches and she mentioned to avoid all these medicated patches.