Infused oils contain the medicinal properties of the herbs and flowers that are steeped in them. Other ingredients, such as cayenne, can be infused as well. They are made for external use and are often the base for salves, ointments, balms, etc.
I make infusions using the guidelines in Richo Cech’s book, Making Plant Medicine, 4th Edition [www.herbalreads.com]. Flowers and herbs are steeped in oil, kept at a temperature between 110-120 degrees F. Fresh herbs are processed for 1 week, dried herbs for 2 weeks. During that time, the mixture is stirred once or twice daily. When complete, the infusion is strained into jars and kept refrigerated until used.