Holley Navarre Medical Clinic - Joel Rudman, M.D.
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An Antibiotics Cheat Sheet

With so much dubious information out there on the internet, I thought this might be a helpful guide to educate patients on why doctors choose certain antibiotics for them. Any questions, please come and see us- we are always happy to help you!

THE MAJOR ANTIBIOTICS

PENICILLINS (Amoxil, Pen VK, Augmentin)
PROS: These are extremely good for throat infections and dental problems, like tooth abscesses. Because they are broad spectrum antibiotics (they hit a wide range of pathogenic bacteria), they are useful for the numerous organisms that live and grow in less than sterile areas. A good example would be an animal bite.
Very safe, even for pregnancy. Used extensively in pediatrics.
CONS: It is very easy for bacteria to become resistant to these, only requiring one single mutation to convey resistance. Therefore, in certain settings, penicillin drugs may not work (I tend not to use them for ear infections due to 30% resistance).
DO NOT TAKE IF: allergic to penicillin.

CEPHALOSPORINS (Keflex, Omnicef, Ceclor, Cefzil, Ceftin)
PROS: Broad coverage for a wide variety of infections. Good for throat, ear, sinus, even urinary infections. Keflex usually is the drug of choice for skin infections. It is harder for bacteria to become resistant to cephalosporins as opposed to penicillin.
Safe for pregnancy and kids.
CONS: due to its broad coverage, may actually kill your "good" bacteria, especially the stronger agents like Ceftin. When used unsupervised (without a physician's involvement), may lead to C. difficile infection.
DO NOT TAKE IF: Cephalosporins are cousins of penicillin. Patients that are penicillin allergic have a 20% chance of being allergic to cephalosporins. Therefore, as a rule, I do not write cephalosporins for my penicillin allergic patients.

ZITHROMAX and the MACROLIDES (Erythromycin, Biaxin)
PROS: I separate Zithromax out from the other macrolides because it really is the gold standard of antibiotics. These meds can be used for multiple conditions and are very effective for throat, ear, skin, dental, sinus, and respiratory issues. Zithromax is also easy to take, 6 pills lasting a total of 10 days. Great choice for penicillin allergic patients. Hardly anyone has a true allergy to macrolides. Zithromax is safe for infants and pregnancies.
CONS: The other macrolides, especially Biaxin, are known for GI side effects. If you have a sensitive stomach, you may not like these antibiotics. Biaxin is known for its awful taste. Erythromycin and Biaxin also have some drug interactions that may be important. I would not choose these as my first choice for urinary infections.
DO NOT TAKE IF: you get easily nauseated or have an allergy to erythromycin.

CIPRO AND THE QUINOLONES (Levaquin, Avelox, Floxin)
PROS: very effective for urinary infections. Sometimes used for atypical/resistant sinus infections. Effective when used in combination with Flagyl for intra-abdominal infections (diverticulitis). Levaquin is considered our "biggest gun", and we reserve this for overwhelming infections. I tell patients on Levaquin that it is the last resort to keep them out of the hospital. Extremely useful when used in drops for swimmer's ear. Not many organisms are resistant to it.
CONS: a lot of unfortunate and misguided information out there about side effects. In my experience, side effects are encountered more with haphazard use or using the medicines in a regular, nonchalant way. We are very judicious about when we use quinolones. Not recommended for pregnancy. Cannot be taken by mouth in youth. Expensive.
DO NOT TAKE IF: you are a child (ear drops are OK) or if you are pregnant.

BACTRIM/SEPTRA
PROS: One of only two medicines effective for MRSA. Good for UTIs. OK for acne/skin infections.
CONS: may cause a terrible rash in sensitive patients. Requires a large dose to be effective. Not safe for pregnancy.
DO NOT TAKE IF: you are pregnant or if you have a sulfa allergy.

TETRACYCLINES (Minocin, Doxycycline)
PROS: good for skin infections and acne. OK to use long term. One of only two antibiotics that treat MRSA.
CONS: very weak for most other infections. Cannot be used in young children. Makes people extremely sun sensitive. Cause upset stomach. Not safe for pregnancy.
DO NOT TAKE IF: pregnant.

MACRODANTIN (Macrobid)
PROS: good for certain UTIs. Safe for pregnancy.
CONS: extremely weak, not useful for any other infections.
DO NOT TAKE IF: you are a child or if you have any other infection other than UTI, it will not work.

CLINDAMYCIN (Cleocin) AND METRONIDAZOLE (Flagyl)
PROS: both are used topically for skin issues. Dentists love both because they kill the harmful bacteria that grow in the human mouth. Flagyl is used in combo with Cipro for intra-abdominal infections. Very effective in killing what we call anaerobic bacteria (the things that grow in the colon, the mouth, urogenital area).
CONS: difficult to take due to side effects. Not helpful at all for any other infections (most infections in the sinuses, ears, chest, and skin are caused by aerobic bacteria). Not recommended for youth or pregnancy.
DO NOT TAKE IF: you have a standard, run of the mill throat, chest, skin, urine, ear, or sinus infection. These antibiotics are for specific problems only.

A brief summary of the usual indications for each drug:
EAR INFECTIONS- Zithromax, penicillins, cephalosporins
THROAT- penicillins
SINUS (acute)- Zithromax, penicillins, cephalosporins
SINUS (chronic)- Penicillins, quinolones
SKIN- tetracyclines, Keflex, Bactrim, topical clindamycin
BRONCHITIS- Zithromax, penicillins
PNEUMONIA- Augmentin, Levaquin
ATYPICAL CHEST INFECTIONS- Zithromax, Doxycycline
UTI- Bactrim, Macrobid, Cipro
DENTAL-PCN, Clindamycin
MRSA- tetracycline or Bactrim
GI infections- PCN, flagyl plus Cipro
STD- Zithromax, Penicillin
LIFE THREATENING- Levaquin