Generic Name: clindamycin

Brand and Other Names: Cleocin, Cleocin Pediatric

Drug Class: Antibiotics, Lincosamide

What is clindamycin, and what is it used for?

Clindamycin belongs to a class of antibiotics known as lincosamides, and is used to treat bacterial infections including septicemia, pelvic inflammatory disease, abdominal, gynecological, respiratory tract, bone and joint, and skin and skin structure infections. Clindamycin is effective against gram-positive aerobic cocci and most anaerobic bacteria.

Gram-positive and gram-negative bacteria are structurally different and are identified by the Gram stain lab test. Gram-negative bacteria have an additional membrane outside the cell wall that gram-positive bacteria lack. Oxygen is toxic to anaerobic bacteria, while aerobic bacteria can grow in the presence of oxygen because they produce enzymes that detoxify oxygen.

Clindamycin prevents bacterial growth (bacteriostatic) or kills bacteria (bactericidal) depending on the dosage, the type of organism and the site of infection. Clindamycin binds to 50S subunits in the bacterial ribosomes (cellular particles that synthesize proteins) and inhibits the protein synthesis essential for bacteria to grow, by preventing peptide bond formation.

Clindamycin is systemically administered as capsules or injections for most infections, but topical formulations and vaginal preparations can be used for intravaginal or local applications on the skin. Systemic clindamycin is typically reserved to treat severe infections in patients who are allergic to penicillin antibiotics, because of the risk of Clostridium difficile colitis. Clindamycin kills most of the healthy bacteria in the gastrointestinal tract, allowing overgrowth of C. difficile, which is not susceptible to Clindamycin, resulting in colitis.

Systemic clindamycin is used to treat bacterial infections including:

Topical applications:

Off-label uses:

Bacteria susceptible to clindamycin include: Staphylococcus aureus (methicillin-susceptible strains), Streptococcus pneumoniae (penicillin-susceptible strains), Streptococcus pyogenes, Prevotella melaninogenica, Fusobacterium necrophorum, Fusobacterium nucleatum, Peptostreptococcus anaerobius, and Clostridium perfringens.


  • Do not use clindamycin in patients with hypersensitivity to clindamycin, lincomycin and any of their components
  • Clindamycin can cause Clostridium difficile associated diarrhea (CDAD) that may range from mild diarrhea to fatal colitis; surgical removal of affected portions of colon (colectomy) may be required
  • Consider possibility of clostridium difficile in all patients who present with diarrhea following antibiotic use; in case of suspected or confirmed CDAD:
    • All antibiotics excluding those directed against C. difficile must be stopped
    • Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted
  • Clindamycin contains benzyl alcohol as a preservative. Benzyl alcohol has been associated with a fatal "gasping syndrome" in premature infants
  • Clindamycin should not be used to treat meningitis, because it doesn’t diffuse well into cerebrospinal fluid
  • Serious anaphylactic reactions must be treated immediately with epinephrine, and if required, oxygen and intravenous corticosteroids
  • Clindamycin is potentially toxic to the kidney; use with caution in patients with kidney function impairment or those on other drugs that may affect the kidneys
  • When used as prophylaxis for endocarditis, use only for high-risk patients, per American Heart Association (AHA) guidelines
  • Use clindamycin with caution in patients:
    • With a history of gastrointestinal diseases, especially colitis
    • With impaired liver function
    • Prone to allergies (atopic)
  • Prolonged use of clindamycin can cause superinfection of nonsusceptible organisms, both fungal and bacterial
  • Discontinue clindamycin permanently if severe skin reactions such as drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome and toxic epidermal necrolysis occur
  • In the absence of a proven or strongly suspected bacterial infection or a prophylactic indication, clindamycin is unlikely to be beneficial and increases the risk of development of drug-resistant bacteria


Bacterial Infections 101: Types, Symptoms, and Treatments See Slideshow

What are the side effects of clindamycin?

Common side effects of clindamycin include:

Rare side effects include:

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug.

Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

What are the dosages of clindamycin?


  • 75mg
  • 150mg
  • 300mg

Injectable solution

  • 150mg/ml

Oral solution

  • 75mg/5ml

Intravenous ready-to-use solution

  • 300 mg/50mL (5% dextrose)
  • 600 mg/50mL (5% dextrose)
  • 900 mg/50mL (5% dextrose)



Aerobic gram-positive cocci and the more susceptible anaerobes (NOT generally including Bacteroides fragilis, Peptococcus species and Clostridium species other than Clostridium perfringens)

  • 600–1200 mg/day intravenous/intramuscular (IV/IM) divided 2-4 times a day

More severe infections, particularly those due to proven or suspected Bacteroides fragilis, Peptococcus species, or Clostridium species other than Clostridium perfringens

  • 1200–2700 mg/day IV/IM divided 2-4 times a day

For more serious infections, these doses may have to be increased; in life-threatening situations due to either aerobes or anaerobes these doses may be increased to doses of as much as:

  • 4800 mg per day given as IV to adults

Single intramuscular injections of more than 600 mg is not recommended

Alternatively, drug may be administered in the form of a single rapid infusion of first dose followed by continuous IV infusion as follows:

  • To maintain serum levels higher than 4mcg/mL, administer a rapid infusion at 10 mg/minute for 30 minutes followed by maintenance infusion of 0.75 mg/minute
  • To maintain serum levels higher than 5 mcg/mL, administer a rapid infusion at 15 mg/minute for 30 minutes followed by maintenance infusion of 1 mg/minute
  • To maintain serum levels higher than 6 mcg/mL, administer a rapid infusion at 20 mg/minute for 30 minutes followed by maintenance infusion of 1.25 mg/minute

Serious Infections Caused by Anaerobic Bacteria

  • Adult: 150-450 mg orally every 6-8 hours; not to exceed 1.8 g/day, OR
  • 1.2-2.7 g/day IV/IM divided every 6-12 hours; not to exceed 4.8 g/day


  • 450-900 mg IV every 8 hours

Inhalational And Gastrointestinal Anthrax (Off-label)

  • 900 mg IV every 8 hours with ciprofloxacin 400 mg orally every 12 hours or doxycycline 150-300 mg orally every 12 hours

Bacterial Vaginosis

  • 300 mg orally every 12 hours for 7 days

Surgical Prophylaxis

  • 900 mg oral/IV 1 hour prior to the procedure; may re-dose every 6 hours if necessary

Bite Wounds (Human or Animal)

  • 300 mg orally every 6 hours

Gangrenous Pyomyositis

  • 900 mg IV every 8 hours with penicillin G

Group B Streptococcus

Neonatal prophylaxis

  • 900 mg IV every 8 hours until delivery

Orofacial/Parapharyngeal Space Infections

  • 150-450 mg orally every 6 hours for at least 7 days; not to exceed 1.8 g/day, OR
  • 600-900 mg IV every 8 hours

Pelvic Inflammatory Disease

  • 900 mg IV every 8 hours with gentamicin 2 mg/kg; THEN 1.5 mg/kg every 8 hours; continue after discharge with doxycycline 100 mg orally every 12 hours to complete 14 days of therapy

Toxic Shock Syndrome

900 mg IV every 8 hours plus oxacillin or nafcillin (2 g IV every 4 hours) or vancomycin (30 mg/kg/day IV divided every 12 hours)

Endocarditis Prophylaxis (Off-label)

  • 600 mg oral/IV/IM 30-60 minutes before procedure
  • Avoid IM injections in patients receiving anticoagulant therapy; administer orally in these circumstances; in general, administer IV only if the patient does not tolerate or is unable to absorb oral medications
  • Dosing considerations: Recent AHA guidelines recommend only for high-risk patients undergoing invasive procedures

CNS Toxoplasmosis, With Pyrimethamine or Leucovorin (Off-label)

  • 600 mg IV or orally every 6 hours for at least 6 weeks

Gardnerella Vaginalis (Off-label)

  • Oral: 300 mg orally every 12 hours for 7 days

Pneumocystis (Carinii) Jiroveci (Off-label)

  • 30 mg/kg/day divided every 6-8 hours
  • 300-450 mg orally every 6-8 hours with primaquine for 21 days
  • 600-900 mg IV every 6-8 hours with primaquine for 21 days



Younger than 1 month

  • 15-20 mg/kg/day IV/IM divided three or four times a day
  • Postmenstrual (PMA) age 32 weeks or less: 5 mg/kg IV/IM every 8 hours
  • Postmenstrual age 32 to 40 weeks: 7 mg/kg IV/IM every 8 hours

1 month – 16 years

  • 20-40 mg/kg/day IV/IM divided three or four times a day
  • Dose based on total body weight body regardless of obesity
  • Alternatively, it may be administered on the basis of square meters body surface: 350 mg/m2/day for serious infections or 450 mg/m2/day for severe infections
  • May change parenteral therapy to oral therapy when condition warrants and at discretion of physician

Serious Infections Caused by Anaerobic Bacteria

Younger than 7 days

  • Less than 2 kg (or younger than 7 days, less than 1.2 kg): 10 mg/kg/day IV/IM divided every 12 hours  
  • More than 2 kg (or younger than 7 days, 1.2-2 kg): 15 mg/kg/day IV/IM divided every 8 hours

Older than 7 days

  • More than 2 kg: 20 mg/kg/day IV/IM divided every 6 hours

Younger than 1 month

  • 15-20 mg/kg/day divided every 6-8 hours

Older than 1 month

  • Hydrochloride: 8-20 mg/kg/day oral
  • Palmitate: 8-25 mg/kg/day divided every 6-8 hours; 37.5 mg every 8 hours minimum palmitate dose


  • 15-40 mg/kg/day IV divided every 6-8 hours  
  • 8-25 mg/kg/day oral divided every 6-8 hours



  • 20 mg/kg orally 30-60 minutes before procedure, OR  
  • 20 mg/kg IV/IM within 30-60 minutes before procedure

Streptococcal Pharyngitis

  • May consider use in patients allergic to penicillin (IDSA guidelines)
  • Chronic carrier treatment: 20-30 mg/kg/day orally divided every 8 hours; not to exceed 300 mg/dose
  • Acute treatment in penicillin-allergic patients: 7 mg/kg/dose three times a day for 10 days; not to exceed 300 mg/dose  

Orofacial Infections

  • 10-20 mg/kg/day orally divided every 6-8 hours, OR  
  • 15-25 mg/kg/day IV divided every 6-8 hours
  • May adjust dose as necessary not to exceed 40 mg/kg/day

Dosing Considerations

  • IM: No more than 600 mg per injection
  • Endocarditis: Recent AHA guidelines recommend only for invasive procedures in high-risk patients


  • Oral: May take with food


Bowel regularity means a bowel movement every day. See Answer


  • Clindamycin overdose typically causes gastrointestinal symptoms, however, animal studies show that high doses of intravenous drug may cause convulsions.
  • There is no antidote for clindamycin; treatment is reduced dosage or discontinuation of the drug, and symptomatic and supportive care.

What drugs interact with clindamycin?

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

  • Clindamycin has no known severe interactions with other drugs.
  • Serious Interactions of clindamycin include:
  • Moderate Interactions of clindamycin include:
  • Mild Interactions of clindamycin include:
    • balsalazide
    • biotin
    • erythromycin base
    • erythromycin ethylsuccinate
    • erythromycin lactobionate
    • erythromycin stearate
    • pantothenic acid
    • pyridoxine
    • pyridoxine (Antidote)
    • thiamine

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.

Pregnancy and breastfeeding

  • Clinical trials of clindamycin use in second and third trimesters of pregnancy do not show any evidence of fetal harm; animal studies do not reveal no fetal harm in the first trimester, however, there are no well-controlled studies in women in the first trimester; use clindamycin only if clearly needed
  • Clindamycin is present in breast milk: avoid use in breastfeeding patients if possible; monitor breastfeeding infants for gastrointestinal disturbances, diarrhea, and bloody stools if maternal treatment is required

What else should I know about clindamycin?

  • Take clindamycin exactly as directed by your physician
  • Complete the prescribed antibiotic therapy; do not skip doses or discontinue therapy if you feel better; it can decrease effectiveness of treatment and can also lead to development of drug-resistant bacteria
  • Clindamycin is used only for bacterial infections; do not use for viral infections
  • Diarrhea is a common problem with antibiotic treatments which should resolve with the completion of the therapy; seek medical help if you have watery or bloody stools, with or without stomach cramps and fever; can develop even up to two months after the last dose of antibiotic

Subscribe to MedicineNet's General Health Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.


Clindamycin is an antibiotic used to treat bacterial infections including septicemia, pelvic inflammatory disease, abdominal, gynecological, respiratory tract, bone and joint, and skin and skin structure infections. Common side effects of clindamycin include abdominal pain, nausea, vomiting, diarrhea, skin reactions, jaundice, abnormal liver function test results, and others. Use clindamycin during pregnancy only if clearly needed. Avoid use when breastfeeding if possible.

Treatment & Diagnosis

Health Solutions From Our Sponsors

FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Medically Reviewed on 4/21/2022