Miscellaneous Antibiotics

Nitrofurantoin

       Nitrofurantoin is a drug that is only useful for urinary tract infections.  It covers most bacterium (including E. Coli) that cause urinary tract infections.

     This antibiotic does not cover common bacterium that cause urinary tract infections in men and some older women.  It is therefore recommended to be used only for uncomplicated urinary tract infections in young women.

     It should not be used in those who have kidney problems or who do not make urine.  Individuals with a G6P deficiency should not use this drug.  It has not been studied thoroughly in pregnancy and should be used with caution in pregnant women. 

     The extended release form is typically dosed 100 mg taken twice a day for 7 days.  The standard form is dosed four times a day in the treatment of urinary tract infections. 

     Nitrofurantoin (Macrobid) has no significant serum level and has been used extensively in the management of UTIs.  It does requires 7 days to treat uncomplicated UTIs.  This is opposed to many of the other antibiotics used in the treatment of UTIs being a three-day course.

     Common side effects include:

• Nausea
• Dizziness
• Headache

     Those who use it long-term may be afflicted with lung or blood disorders.  Therefore, monitoring kidney and lung function is critical in those who use this drug long-term.  It is used long-term in the suppression of recurrent UTIs. 

Rare side effects include:

• Liver failure
• Severe rash
• Damage to the optic nerve

Metronidazole

     Metronidazole (Flagyl) is a drug that is given orally, intravenously, topically or intra vaginally.  It covers anaerobic bacteria.  Anaerobic infections are unique infections that cause problems in the stomach, mouth or vagina.  This medication also provides some anti-protozoal activity.  It is used for:

• Bacterial vaginosis (a vaginal infection that presents with a vaginal discharge and a fishy odor) 
• Diarrhea secondary to Clostridium difficile or giardia lamblia
• Pelvic inflammatory disease (with other antibiotics such as quinolones)
• Intra-abdominal abscess
• Peritonitis (infection in the stomach)
• Diabetic foot ulcer
• Brain abscess
• Acne rosacea
• Trichomonas vaginalis  (a sexually transmitted disease that presents with greenish-yellow vaginal discharge and vaginal itching)
• Helicobacter pylori (bacteria that causes stomach ulcers)  - it is not used as a first-line drug
• Acute gingivitis/dental abscess
• Pneumonia, lung abscess or aspiration pneumonia.  Aspiration pneumonia occurs when there is a oral or gastrointestinal fluid that gets into the lungs and causes infection.  It is more common in those who are older and have problems with swallowing.  Individuals who are drunk and throw up can be afflicted with aspiration pneumonia. 

Side effects

     Common side effects (with oral therapy)

• Nausea
• Diarrhea
• Metallic taste in the mouth

Uncommon side effects include:

• Rash
• Fever
• Seizure
• Itching
• Dizziness
• Vomiting
• Headache
• Numbness
• Inflammation of the tongue

Long-term use of metronidazole may cause:

• Low white blood cells
• Black hairy tongue
• Nerve damage
• Possibly increase the risk of cancer (only shown in animals)

Topical therapy is associated with:

• Redness
• Skin irritation
• Dry skin
• Eye watering if put near the eyes

     This antibiotic should NOT be consumed with alcohol.  It can cause a severe reaction that presents with nausea, vomiting, increased heart rate, flushing of the skin and shortness of breath.  No alcohol should be drunk while the patient is on the antibiotic and for two days afterwards. 

Clindamycin

     Oral clindamycin is available as a generic and under multiple trade names, including: Clindacin, Cleocin, and Evoclin.   It is also available in topical form – combined with benzoyl peroxide in products called: Duac and BenzaClin.           

     It is used for many of the same infections that are responsive to penicillin.  It is not used as a first-line medication most of the time because it is associated with more side effects.  It is used in some specific infections and in those with multiple antibiotic allergies.   Clindamycin treats infections with anaerobic bacteria and some non-bacterial infections such as malaria.

     Common reasons it is used include:

• Acne (especially in topical form)
• Skin infections including methicillin-resistant Staphylococcus aureus (MRSA) infections
• Bacterial vaginosis during early pregnancy – treatment with Clindamycin reduces risk of premature births
• Respiratory tract infections
• Bone and joint infections 
• Peritonitis
• Serious infections such as toxic shock often in combination with vancomycin (a powerful IV drug)

Side effects

     A serious side effect is Clostridium difficile-associated diarrhea.  While any antibiotic can lead to this infection, it is very common with clindamycin.  The incidence of Clostridium difficile-associated diarrhea is one of the main reasons that this drug is not used often for infections. 

     Other common side effects include:

• Nausea
• Vomiting
• Abdominal cramps
• Abdominal pain
• Itching
• Rash
• Metallic taste (high doses)
• The topical formulation can cause redness of the skin
• Rare side effects include: liver toxicity, arthritis, blood disorders and breathing difficulty