When a pain killer is taken, how does the it know on which part of the body it should act ?

Answer 1

It does not! Pain killer act systemically, i.e. in the whole organism, and decreases pain as well as inflammation (as most of these drugs are also anti iflammatory drugs) wherever they are.

Most cells are not responsive to them because they will not express the proteins that cause pain / inflammation and which are targeted by the pain killers. A good example is Aspirin reducing pain and inflammation by inhibiting COX1 and COX2 (proiflammatory enzymes) expression.

Answer 2

Painkilling drugs can act in several ways, however they usually act on enzymes involved in the production of hormones. A common example is the group of COX inhibitors. They prevent the production of certain eicosanoids which tell the body that it is in pain.

Drugs you can buy at the drug store do not usually act directly on nerves or the nervous system, including the brain. They instead prevent the process by which pain is reported to the nervous system.

This means, as several people have said, that drugs often prevent lots of pain that you could potentially feel, although you generally take it to prevent a specific discomfort. If drugs enter your bloostream, they go everywhere. If they do not reach the bloodstream, they diffuse slowly and reach only a limited area.

Answer 3

Most painkillers act on the nervous system.They either block pain sensation from travelling to the brain or block the brain from feeling the pain. The pain killers travel to all parts of the body but only act only on specific sites such as nerves.

Answer 4

Where does the pain emnate from-the brain, I think. I think the pain killer just 'deadens' some nerves for some time. It is a temporary relief, and is best avoided until the pain is excriciating.

Answer 5

It does not know. It travels everywhere in the bloodstream till it hits the relevant part of body. That is why drugs have side effects .

Answer 6

Oral/intervenous pain killers universally act on the
nervous system and the brain. It has nothing to do
with which thing is hurting. They inhibit pain
everywhere in your body.

If only one thing hurts, then only one thing is
going to feel better.

"topical" pain killers are applied directly to the thing
that hurts - and then they usually act on the local
nervous system.

Answer 7

It only act on your brain only. The part where we feel pain. We feel the pain because our brain said so.

Answer 8

It enters the blood stream, and circulates! The part of body that needs it, uses it! (like you catch a bus from a bus stop!)

Answer 9

Generally doctors advise to take medicines after meal to save ourself from their side effects.

Answer 10

painkillers are nothing else but the chemicals which are meant to target the particular cells in the body. these chemicals are very cell -specific.