Re: abcessed tooth infection went into Central Nervous System
I'm sorry you've been feeling so unwell, but I'm glad that things are starting to look up. First off, you're right, long lasting dental infections can have complications and one of those is involvement of the central nervous system. Because the veins in the face are valveless, infections can spread fairly quickly and extensively over a relatively short period of time. Addtionally, because of the proximity to the CNS, dental infections can go on to cause certain complications such as deep neck space infections, infections of the jugular vein (known as septic thrombophlebitis), cavernous sinus thrombosis, meningitis, brain abscesses etc. etc.
That all said, when that happens, the person is VERY sick. We are not talking about someone who is able to type on healthboards.com....we're talking about someone who has high fevers and disabling symptoms which require hospitalization (possibily in an ICU setting).
If a dental abscess is extensive enough, the best treatment for it is surgical to drain the abscess and/or remove the tooth ALONG with antimicrobial therapy. Antibiotics which cross the blood/brain barrier are necessary only if there is evidence that the infection has entered the bloodstream (which I doubt in your case) or if there is objective visualization of some suppurative (i.e. pus containing) extension of the dental abscess to an area in or close to the CNS.
To answer your question: antibiotics which cross the blood/brain barrier which would be applicable in someone who has an oral infection with CNS extension are the beta-lactams. This includes essentially all the members of the penicillin and cephalosporin groups. Often when people have brain abscesses originating from the mouth, ID doctors use garden variety penicillin G sometimes along with metronidzaole. The quinolones (i.e. levofloxacin) don't cross the BBB very well; however, in your case, you probably don't need something that does. Incidentally, clindamycin is another great antibiotic for oral infections and it DOES cross the BBB.
One other thing you should know is that when someone has an infection which has reached any level of chronicity (i.e. has been going on for more than a week or two) a lot of the "unwellness" you feel is not from the infection itself, but your immune system's response to it. The immune system begins to go in to chronic inflammatory mode and the cytokines which are released in this process can cause anyone to feel very sick. Unfortunately, even when the infection is gone, sometimes it take a bit for the immune system to shut off and you can feel unwell for a few weeks after. Keep this in mind when you're on the antibiotics because you may not begin to feel 100% right away.
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