Why do doctors administer injection through vein?

Answer 1

Easier to do so! thats why

For your question we have to compare between arterial (intraarterial) injections and venous injections(specifically intravenous or IV).
Although there exist other types of injections like intramuscular(given into muscles), Subcutaneous(just below the skin) ,dermal (pricking on the skin for allergy tests) etc

First of all the veins are much more superficial than the arteries thus are easier to detect (on the hand for example).
Arteries are deeply situated and thus administration of drug is risky.

Besides when drug is administered in a vein, it goes to the heart and is then circulated uniformly throughout the body.
Whereas for the same purpose (for an artery) you would have to give injection in the AORTA which is very hazardous!

Answer 2

If your question is regarding why injections are more commonly in the vein (intraveuous) as compared to the artery (intraarterial), the vein route is prefered because the injection will pass through the lungs prior to going to the heart. This is because any air that is trapped in the injection will have time to leave then passing through the lungs prior to reaching the heart. Trapped air can have serious consequences.

However, not all drugs are administered intravenously.

There are many things to consider:

-How quickly does the drug need to get through the system. Injecting right to the blood stream via a vein/artery the fastest route. Used for saline to treat dehydration, a lot of caner therapies, some injections of antibiotics, etc.)

-Volume of injection. If large volume are needed, IV is the way to go. Only a few mls at time can be administered subcutaneously (under the skin) or intramuscular (into the muscle).

-Ease of administration: Subcutaneous can be done by yourself (e.g. insulin shots are given by the patient usually). Intramuscular shots typically require administration by a trained professional (e.g. vaccines) as do intravevnous administrations.

-Oral administration is used when possible, but a lot of new therapies coming out are destroyed in the digestive tract, and not used at all for protein therapeutics (your body will digest them like a piece of steak).

-Nasal administration is becoming more popular. New form of insulin now available using this route.

The easiest route of administration is preferred, but all things are considered for the particular drug and use.

Answer 3

I give people intravenous medications every day. I'm an anesthesiologist, and I give everything IV so that it will work quickly. Medications given by mouth take about 20 minutes to work, and the absorbtion is unpredictable. When I give IV injections, I know how much drug is getting in and that it will work in seconds to minutes (depending on the medication).

Sometimes drugs like antibiotics need to be given IV to get high blood levels quickly to treat severe or resistant infections. There are other drugs that cannot be given orally because the digestive system will break the drug down.

Hope that helps answer your question.

Answer 4

this is only one way an injection can be done . the reason an injection would be directly into a vein is the need for the drug to reach the blood stream immediately . the drug is not absorbed well through the skin. the drug is designed only to work when given in that manner.

Answer 5

It is the fastest way to get the drug into the blood stream, and as soon as it is in the blood, it can take it's effect immediately. The vein is the quickest point of access to the bloodstream.

Answer 6

because they're closer to the surface, they have lower pressure, and the injected solution is distributed through the body faster.
besides, stick a needle in an artery, and you might get blood spraying around. not what you want.

Answer 7

For faster action or a compound not easily absorbed. Believe me it is not easier by any means.

Answer 8

not all injections go into veins some go into muscle

Answer 9

because the blood is carried throughout the bod. and that's where the meds go