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
1. The skin is a good barrier. It is difficult to get drugs through it, the moleclue must among other things be small enough for it.
2. Cost. You mentioned levothyroxine, which dosage is adjusted according to the persons blood tests. This would require a wide variety of different strhengts on the market, which would cost a lot to develop and thus cost a lot for the consumer.
We do. Transdermal patches for everything from opiates to nicotine.
Hormone implants are common but they also use cetain implants for things like treating alcoholism, and anti-psychotic meds often use this method of delivery when compliance is a concern.
These are common methods across pharmaceuticals, but they increase the cost significantly enough that traditional methods like daily pills are preferred.
[removed]
It is a big thing that the dynamics of the medication need to be preserved. So some medications have certain enzymes or chemicals they have to come in contact to cause a shape or chemical change to make them active in the right place at the right time. If they do not come in contact they may not work or that can do things we do not want them to do. This is why side effects can exist. This is also why some pill shapes are differently shaped so they can change the way the pill is broken down. Some medications can only be absorbed in certain parts of your GI tract.
For example most doors need a key, you cannot use brick of iron you found in the ground, the iron needs to be shaped into the right shape in order to go into the right lock. So medications often fit into a key hole or a receptor that causes an action. If we put them through the skin, they may not be shaped correctly, or they may not even end up at the right house.
Some places we give medication may melt down that iron in a way we can’t use it in making a key at all. So we have to avoid those mechanisms that ruin the medication before it reaches its site of action. Skin also can have a variable makeup of medication, think of someone with literal thick skin. Birth Control implants release very small amount of medication, so a small implant can hang around for a long time releasing very small dosages of medication that are very strong pieces of iron. Levothyroxine acts on a very busy part of the body, the thyroid, which can have fluctuations in its function from day to day activities. So one consistent dose will not work all the time , and manufacturing a patch for a single person would be hard. In addition that medication given through the skin may be incapable of making it to the thyroid to fit in the right keyhole.
The last thing is that the medication may damage the skin itself depending on its makeup. our skin and body tissues have different makeups everywhere so it is like how some ovens are made of iron, or brick. I should not use a wooden oven in my house, it would burn down. But I can use a brick oven to shape the iron into the right shape without damaging my house.
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
Nobody is developing that for you because they know the following:
Levothyroxine (LT4) is very sensitive, unstable material. It would probably not stay active in a patch.
LT4 monthly dose is about 4000 milligrams for an average person. A patch usually can hold a few milligrams of substance. A birth control patch has less than 1 milligram in it, a nicotine patch is about 25. So the patch capacity is way too low.
Skin patches work well with hydrophobic substances, aka things that dissolve in oil but not in water. Nicotine and estradiol are such, LT4 is the opposite.
But there are actual efforts to develop improved LT4 delivery methods, so hopefully you will get something better. Unfortunately, as I said, LT4 is complicated.
Latest Answers