Suggest Remedy For Red Bumps On Mid Section

Hello, I have very small barely visible, barely red bumps on my mid section that at times feel like little pin pricks. They seem most active when I'm stressed (very often) or exposed to say a jacuzzi or hot water. They have been around for several months, are tolerable but annoying and are nowhere else on my body. If I don't point them out to someone, I could go without a shirt and they wouldn't notice. I'm 51 years old and in otherwise excellent health.