Eli5 how come we can have transdermal patches and implants that last for months for things like birth control but not for other drugs

Question

I’m thinking things like levothyroxine that people have to take every day and are really important not to miss. Why can’t we have an implant or patch for this? It would be really helpful and possibly save lives.

In: 16

Answer 1

The biggest thing is that it only works for drugs that have certain properties. The drug has to be able to “dissolve” in skin cells in order to get through them and into your body. Most drugs are dissolvable in water, but are not as dissolvable in the more oil-like cells. Birth control are hormones, and hormones have to get inside cells to work. So if they are able to get inside cells in your body, they should also be able to go through your skin cells, too