How do antibiotics know where to go?

[scilearner]

Hello everyone,

 

Let's say I have a throat infection and all the bacteria are near the throat. I get antibiotics. So if these antibiotics enter bloodstream, how do they know they have to diffuse out right near the throat area. Are they diffusing all the time, going to unwanted places. Why is it bad to get antibiotics frequently, I can understand they will kill good bacteria, but how does this create antibiotic resistance to bad bacteria. Thanks

[Greippi]

They diffuse throughout the blood stream, and when they meet a target they bind to it. They don't neccessarily localise to the throat. Also, just because inflammation is seen only in the throat, it doesn't mean that the bacteria are only present there.

 

Antibiotic resistance put simply:

You have a population of bacteria, all with slightly different genes (normal variation within a population). They will all have slightly varying susceptibility to being killed by the antibiotics. The ones with high sensitivity to antibiotic will be killed off first. The ones with more resistance that survive longer have time to replicate, so you get more bacteria present with higher resistance. And so on... - don't forget that these bacteria can spread to other people too. eventually you get a pool of bacteria that are completely resistant to antibiotic.

[scilearner]

Thanks Grieppi So if they diffuse everywhere, when it comes to important area like throat in this case, could there be less antibiotical agents. I mean sometimes can they be wasted going to unnessecary areas or is the quantity always enough.

[Greippi]

You have lymph nodes in your throat region. All blood/fluids drain in the lymph nodes and this is a primary site for cells of your immune system to encounter infection. This is why your throat gets swollen. The bacteria isn't necessarily JUST in your throat, but that's where you're seeing the signs of inflammation because that's where some lymph nodes are. Circulating the antibiotic around the body maximises the chance it'll catch all the bacteria.

 

Orally administrated antibiotics reach a perfectly effective concentration for killing a bacterial infection. For more resistant/severe infection antibiotics can be administered directly into the blood stream.

[scilearner]

You have lymph nodes in your throat region. All blood/fluids drain in the lymph nodes and this is a primary site for cells of your immune system to encounter infection. This is why your throat gets swollen. The bacteria isn't necessarily JUST in your throat, but that's where you're seeing the signs of inflammation because that's where some lymph nodes are. Circulating the antibiotic around the body maximises the chance it'll catch all the bacteria.

 

Orally administrated antibiotics reach a perfectly effective concentration for killing a bacterial infection. For more resistant/severe infection antibiotics can be administered directly into the blood stream.

 

Thanks again Is all fluid drained from lymphatic system or isn't it only some part of interstitial fluid that is drained from lymphatic system at one time. Or did you mean that eventually all fluid would be drained.

[ewmon]

The body does tend to divert wound-plugging and infection-fighting materials to the damaged areas by simply dilating the blood vessels in the area, which naturally allows more of everything to go there, including the red blood cells. The "redness" of damaged areas (ie, infections, sunburns, rug burns, tired eyes, etc) is evidence of increased blood flow to those areas.

 

Sunburns are warm because they have more of your 98.6°F/37°C blood at the surface ... the same as cold ears, noses, fingers, toes, etc in cold weather to keep them warm. What you don't want to see in cold weather is exposed white parts, which indicates frozen/dead tissues.