Clindamycin is a strong broad-spectrum antibiotic, typically prescribed for serious infections, such as life-threatening methicillin-resistant Staphylococcus aureus (MRSA) skin infections.

It casts a wide net and is effective against a host of bacterial infections, including gram-positive organisms such as Staphylococcus aureus (methicillin-susceptible strains), Streptococcus pneumoniae (penicillin-susceptible strains), Streptococcus pyogenes and some gram-negative ones. It is also effective against several anaerobic bacteria, which are those that survive without air.

Clindamycin treats many categories of bacterial infection, including:

• Severe respiratory infections
• Severe skin and soft tissue infections
• Bloodstream infection (sepsis)
• Pelvic or genital infections
• Abdominal infections

It is sometimes used to treat acne, anthrax, malaria, ear or throat infections, or toxoplasmosis. It may also be prescribed as a prophylactic in those at risk of heart infection (endocarditis) from a dental procedure.

Broad-spectrum antibiotics like clindamycin are powerful and can reach many areas of tissue and many types of bacteria in your body. This can lead to two issues:

• Broad-spectrum antibiotics are more likely to cause short-term and long-term problems in the gut system.
• The overexposure to antibiotics in the body can promote antibiotic resistance.

In contrast, narrow-spectrum antibiotics such as older penicillin-based antibiotics, the macrolide class and vancomycin have more specific targets and are less likely to cause issues in the gastrointestinal tract.

Clindamycin does confer its share of side effects, including, among others:

• Nausea
• Vomiting
• Diarrhea
• Vaginal discharge and burning

Infection with Clostridium difficile (C. diff) is possible with clindamycin (and all antibiotics), which can cause severe diarrhea and an inflammation of the colon (colitis) and may occur more frequently with clindamycin compared to other antibiotics. This is a serious infection, but the risk is still low even with clindamycin use.

Symptoms of C. diff include:

• Frequent watery or bloody diarrhea
• Severe stomach pain
• Low-grade fever
• Loss of appetite
• Nausea

Resistance can make certain antibiotics less powerful over time against certain infections. Resistance occurs when an antibiotic that previously cured an infection doesn’t work as well or at all anymore. This may occur due to over- or indiscriminate use of antibiotics, which is why it’s important to take antibiotics only as directed for as long as directed. Many germs are now resistant to penicillin and other antibiotics, and some are becoming resistant to clindamycin, lowering its strength against certain infections.