Generic Name: chloramphenicol
Brand and Other Names: chloramphenicol IV, Chloromycetin (discontinued)
Drug Class: Antibiotics, Other
What is chloramphenicol, and what is it used for?
Chloramphenicol is a synthetic broad-spectrum antibiotic used to treat severe systemic infections caused by susceptible strains of bacteria. Chloramphenicol topical formulations were used in the past to treat superficial eye and ear infections.
Because of its serious adverse effects, oral and topical chloramphenicol formulations are no longer available in the U.S. and intravenous chloramphenicol is used only for acute and serious infections that cannot be treated with less toxic alternative antibiotics.
Chloramphenicol prevents bacterial growth by binding to the bacterial ribosomes (cellular particles that synthesize proteins) and preventing the protein synthesis essential for the bacteria to grow. This damages the bacterial protein and cell membrane, resulting in bacterial death.
Chloramphenicol is effective against a wide range of gram-positive and gram-negative bacteria. Gram-negative and gram-positive bacteria are structurally different, and the types are identified by whether the bacteria get dyed or not in the Gram stain lab test.
Chloramphenicol is used for the treatment of serious infections including:
- Bacterial meningitis
- Bacterial blood infection (bacteremia)
- Typhoid fever
- Rickettsial infections
- Exacerbation of cystic fibrosis
Organisms susceptible to chloramphenicol include:
- Salmonella typhi and other Salmonella species
- Haemophilus influenzae
- Rickettsia species
- Chlamydiaceae
Warnings
- Do not use chloramphenicol in the following circumstances:
- In patients who have had previous hypersensitivity or toxic reaction to it
- Trivial bacterial infections
- Viral infections
- For prevention (prophylaxis) of bacterial infections
- Chloramphenicol can cause bone marrow suppression (myelosuppression) that may result in serious and fatal blood disorders (dyscrasias) after both short-term and long-term therapy; use only for serious infections, monitor complete blood count (CBC) frequently and discontinue upon evidence of myelosuppression
- Avoid repeated courses of chloramphenicol therapy, if at all possible
- Do not continue treatment longer than required to cure the disease with little or no risk of relapse of the disease
- Elevated blood levels of chloramphenicol in infants can lead to gray baby syndrome, characterized by grayish skin, abdominal distention, and circulatory collapse that can lead to death; premature infants and newborns are at the highest risk because their kidneys and liver are immature and not fully functional; use with extreme caution
- Prolonged use may result in fungal or bacterial superinfection; monitor and take appropriate measures if nonsusceptible organisms appear
- Impaired liver or kidney function may cause excessive blood levels of chloramphenicol even at recommended dose; determine blood concentration at appropriate intervals and adjust dosage accordingly
- Use with caution in patients with glucose 6-phosphate dehydrogenase deficiency

SLIDESHOW
Bacterial Infections 101: Types, Symptoms, and Treatments See SlideshowWhat are the side effects of chloramphenicol?
Common side effects of chloramphenicol include:
- Bone marrow depression
- Blood disorders, including:
- Anemia due to lack of red blood cell production (aplastic anemia)
- Anemia from inadequate red blood cell production (hypoplastic anemia)
- Low blood count of granulocyte immune cells (granulocytopenia)
- Low platelet levels (thrombocytopenia)
- Low count of all types of blood cells (pancytopenia)
- Headache
- Confusion
- Delirium
- Depression
- Nausea
- Vomiting
- Diarrhea
- Intestinal inflammation (enterocolitis)
- Inflammation of oral tissue (stomatitis)
- Inflammation of the tongue (glossitis)
- Inflammation of the optic nerve (optic neuritis)
- Skin rash
- Hives (urticaria)
- Swelling of the tissue under the skin and mucous membranes (angioedema)
- Severe allergic reaction (anaphylaxis)
- Fever
- Gray baby syndrome
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.
Health News
- Women's Gymnastics Brings High Risk for Concussion
- Going Solo: Masturbation May Give Humans an Evolutionary Edge
- Longer Breastfeeding in Infancy, Better School Grades for Kids?
- Kids With ADHD, Behavior Issues Have Poorer Trajectories as Adults
- FDA Finalizes Limit on How Much Arsenic Can Be in Apple Juice
More Health News »
What are the dosages of chloramphenicol?
Injectable solution
- 1,000 mg/vial
Adult:
Serious Infections Caused by Susceptible Strains
- 50 mg/kg/day intravenously divided every 6 hours
- In exceptional cases, patients with moderately resistant organisms or severe infections may require increased dosage up to 100 mg/kg/day; decrease these high doses as soon as possible
Other Indications and Uses
- Use only as an alternative for treatment of meningitis, typhoid, or rickettsial infection
Pediatric:
Systemic Infections
Infants and children
- As in adults; when adequate cerebrospinal fluid concentrations are desired, may require up to 100 mg/kg/day; however, should reduce dose to 50 mg/kg/day as soon as possible
Infants and children with suspected immature metabolic functions
- 25 mg/kg/day divided every 6 hours will usually produce therapeutic concentrations of the drug in the blood
Neonates (Infants younger than 28 days)
Loading dose (LD)
- 20 mg/kg intravenously once; give maintenance dose 12 hours after loading dose
Maintenance Dose
- Infants younger than 7 days old: 25 mg/kg/day intravenously every 24 hours
- Infants over 7 days old, less than 2000 g: 25 mg/kg/day intravenously every 24 hours
- Infants over 7 days old, over 2000 g: 50 mg/kg/day intravenously every 12 hours
Other Information
- Peaks 10-20 mg/l, troughs 5-10 mg/l
Overdose
- Chloramphenicol overdose can be fatal. Overdose is more likely to affect infants because their liver and kidneys are immature. Symptoms of overdose include
- nausea and vomiting,
- abdominal distension,
- metabolic acidosis,
- hypotension,
- hypothermia,
- cardiovascular collapse,
- coma, and
- death.
- Use utmost precaution to avoid overdose; overdose may be treated with immediate discontinuation of chloramphenicol and intensive supportive care including resuscitation and other life-saving measures.
What drugs interact with chloramphenicol?
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.
- Severe interactions of chloramphenicol include:
- alfuzosin
- aprepitant
- avanafil
- bromocriptine
- eplerenone
- isavuconazonium sulfate
- lurasidone
- pacritinib
- ubrogepant
- voclosporin
- Chloramphenicol has serious interactions with at least 123 different drugs.
- Chloramphenicol has moderate interactions with at least 89 different drugs.
- Chloramphenicol has minor interactions with at least 42 different drugs.
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
- There are no adequate and well-controlled studies on chloramphenicol use in pregnancy; it is not known whether it can cause fetal harm
- Gray baby syndrome has occurred in premature infants and newborns receiving chloramphenicol
- Use chloramphenicol in pregnancy only if the potential benefit outweighs the potential risk to the fetus
- Chloramphenicol is excreted in breast milk; avoid use in nursing mothers; discontinue either the drug or nursing
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.
Summary
Chloramphenicol is a synthetic broad-spectrum antibiotic used to treat severe systemic infections, including bacterial meningitis, bacterial blood infection (bacteremia), typhoid fever, Rickettsial infections, and exacerbation of cystic fibrosis. Common side effects of chloramphenicol include bone marrow depression, blood disorders (including anemia), headache, confusion, delirium, depression, nausea, vomiting, diarrhea, and others. Avoid use in nursing mothers; discontinue either the drug or nursing. Consult your doctor if pregnant.
Multimedia: Slideshows, Images & Quizzes
-
Anemia: Common Causes, Symptoms, Types, and Treatment
Anemia is a disease marked by low numbers of red blood cells. Low iron deficiency or underlying disease, like cancer, may be to...
-
Respiratory Illnesses: 13 Types of Lung Infections
Is your cough caused by a cold, flu, pneumonia or something else? Learn causes of respiratory infection like bronchitis,...
-
Picture of Rickettsialpox (Tâche Noire)
Rickettsialpox or tâche noire is a disease causes by the bite of a mite that lives on mice. It causes a chickenpox like rash that...
-
Meningitis Quiz: Test Your Infectious Disease IQ
What is meningitis and what causes it? Take our Meningitis Quiz to learn the causes, symptoms, treatments, and complications of...
-
Picture of Pernicious Anemia
Pernicious anemia is a disease where large, immature, nucleated cells (megaloblasts, which are forerunners of red blood cells)...
Related Disease Conditions
-
Anemia
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
-
Meningitis
Meningitis is inflammation of the membranes that cover the spinal cord and brain. Symptoms include fever, headache, and a stiff neck. Treatment of meningitis depends upon the cause of the infection and may include antibiotics or antiviral medications.
-
Pernicious Anemia
Pernicious anemia is a blood disorder in which the body does not make enough red blood cells due to a lack of vitamin B12 in the blood. Pernicious anemia can develop from a lack of a protein that helps the body absorb vitamin B12, not getting enough B12 in the diet, and certain intestinal conditions that interfere with the absorption of vitamin B12 such as Crohn's disease, celiac sprue, or ulcerative colitis. There is no cure for pernicious anemia, thus treatment is life-long.
-
Is Meningitis Contagious?
Meningitis, inflammation of the meninges, symptoms and signs include neck stiffness, headache, and fever. There are five types of meningitis: viral, bacterial, fungal, parasitic, and noninfectious.
-
What Foods Are Good and Bad for Your Diet if You Have Anemia?
What is anemia? Learn foods that are good and bad for anemia.
-
How Do You Get Bacterial Meningitis?
Bacterial meningitis is an infection of the tissue surrounding the brain and spinal cord. Learn more about the signs of bacterial meningitis, what causes bacterial meningitis, when to see a doctor, and how to treat bacterial meningitis.
-
What Is the Most Common Cause of Macrocytic Anemia?
The most common causes of macrocytic anemia include vitamin B12 deficiency and folate deficiency.
-
How Quickly Does Meningitis Progress?
Meningitis is an infection of the meninges or coverings of the brain. This serious illness can progress very quickly and have lifelong consequences. So, it is important to get medical attention as soon as possible. The most frequent cause of meningitis is a viral or bacterial infection. Rarely, a fungus can cause it.
-
Typhoid Fever
Typhoid fever is an illness caused by the Salmonella typhi bacteria. The illness is contracted by ingesting the bacteria in contaminated water or food. Symptoms include headaches, fever, diarrhea, lethargy, aches and pains, and poor appetite. Treatment focuses on killing the Salmonella bacteria with antibiotics.
-
Can You Get Cystic Fibrosis at Any Age?
Cystic fibrosis is classically a disease of childhood that progresses into adulthood. If you have a genetic defect related to cystic fibrosis (CF), you are more likely to be born with cystic fibrosis. The symptoms might appear later, and hence, the age at diagnosis varies widely.
-
How Long Does the Meningitis Vaccine Last?
Learn how the meningitis vaccine works and how long it is effective.
-
What Is the Best Treatment for Typhoid Fever?
Learn what medical treatments can help ease your typhoid fever symptoms and speed up your typhoid fever recovery.
-
Anemia: How Is It Treated and Can It Be Cured?
How is anemia treated and can anemia be cured? Learn how to identify and manage anemia.
-
How Often Do You Need to Get the Meningitis Vaccine?
Meningitis is a disease that's defined by inflammation in membranes — called meninges — near your brain and spinal cord. Data is limited, but current research suggests that the MenACWY vaccine becomes unreliable for protection after five years and the MenB vaccine after only one or two years.
-
What Are the 3 Main Causes of Anemia?
Anemia is caused by three main factors: blood loss, low red blood cell production, and red blood cell destruction.
-
What Are the 3 Types of Meningitis?
Meningitis is a serious condition that needs medical attention. Learn about the 3 types of meningitis, what causes meningitis, how doctors diagnose meningitis, and how meningitis is treated.
-
How Long Can You Live With Cystic Fibrosis?
The life expectancy of patients with cystic fibrosis has improved over the last 50 years. The improved chances of survival are due to advances in early diagnosis, supportive care, nutritional care, and infection control.
-
Which Is More Serious: Encephalitis or Meningitis?
What is the difference between encephalitis and meningitis?
-
Encephalitis vs Meningitis: Differences
The diseases, encephalitis and meningitis, have striking similarities with each other. But they differ from each other by a few of their symptoms, causes, their types, and their treatment.
-
What Are Anemia Symptoms During Pregnancy?
Anemia during pregnancy is a common issue that affects many women. Learn the signs of anemia, what causes anemia, how doctors diagnose anemia, and what you can do to treat anemia in pregnancy.
-
How Do You Know if You Have Meningitis?
Meningitis is a potentially life-threatening inflammation of the layers of tissue and fluid that cover the spine and brain. Learn the signs of meningitis, what causes it, how doctors diagnose it, and what you can do to treat it.
-
How Does Anemia Affect Your Baby During Pregnancy?
Anemia occurs when you don't have enough red blood cells to transport adequate oxygen or iron. Anemia during pregnancy may contribute to early delivery or failure of the baby to grow to a healthy weight.
-
How Do You Fix Anemia?
Anemia describes a condition in which you have a low red blood cell count and low hemoglobin levels. This is a serious condition as red blood cells and hemoglobin carry oxygen to all your cells, allowing them to burn energy. If you’re anemic, you’ll likely feel fatigued and short of breath, lacking physical stamina. You may have heart problems and appear pale. Anemia is often a symptom of some other disease or condition, so treatment varies widely depending on the root cause.
-
Cystic Fibrosis Life Span
Cystic fibrosis (CF) is a progressive disease that needs daily care. Though a patient needs to take medications lifelong, most people with cystic fibrosis are usually able to attend school and work. The improvement in screening and treatments mean that people with CF now may live into their mid- to late 30s or 40s, and some are living into their 50s.
-
Can You Live a Long Life With Cystic Fibrosis?
How long can you live with cystic fibrosis? Learn the signs of cystic fibrosis and what to do if someone you know has cystic fibrosis.
-
Where Does Bacterial Meningitis Come From?
Bacterial meningitis is characterized by inflammation around your brain and spinal cord that leads to dangerous — and sometimes deadly — pressure in this area. Bacterial meningitis comes from person-to-person contact with an infected person.
-
What Causes Typhoid Fever?
Typhoid fever is a serious bacterial infection. Learn more about typhoid fever, its symptoms, your treatment options, and possible complications.
-
How Does Anemia Affect Pregnancy?
Anemia is a condition in which your body doesn't make enough red blood cells. The most common type is iron-deficiency anemia which 50% of women develop during pregnancy.
-
What Is the Life Expectancy of Someone Born With Cystic Fibrosis?
Cystic fibrosis (CF) is a genetic disease that causes progressive damage to the organs, especially the lungs and digestive system. People with cystic fibrosis often complete school, including college, have fulfilling jobs, find love, and have children.
-
Meningitis: Symptoms,Treatment, and More
Meningitis is an inflammation of the membrane (meninges) surrounding the brain and spinal cord and is characterized by an abnormal number of white blood cells in the cerebrospinal fluid. Meninges act as a protective layer to the brain and spinal cord.
-
Meningitis Treatment
Meningitis is an inflammation of the membrane (meninges) surrounding the brain and spinal cord and is characterized by an abnormal number of white blood cells in the cerebrospinal fluid. Meninges act as a protective layer to the brain and spinal cord.
-
What Is Macrocytic Anemia?
Macrocytic anemia is a condition in which red blood cells are larger than normal and hemoglobin levels in the blood are low due to increased RBC destruction.
-
What Are the Signs and Symptoms of Bacterial Meningitis?
Signs of bacterial meningitis include sudden onset fever, nausea, vomiting, severe headache, neck stiffness, double vision, confusion, and photophobia.
-
How Do You Treat Anemia in Children?
What are anemia symptoms in children and how do you treat it?
-
What Is Diamond-Blackfan Anemia (DBA)?
Diamond-Blackfan anemia (DBA) is a rare blood disorder that affects the bone marrow. In this condition, the bone marrow fails to make red blood cells, which are essential for carrying oxygen from the lungs to all the other parts of the body. Blood cells are made in the bone marrow.
-
How Is Meningitis Diagnosed and Treated?
If the doctor suspects you have meningitis, you will be hospitalized immediately for proper testing and to manage the illness. The treatment and care will depend on the type of meningitis the patient has and how unwell the patient is.
Treatment & Diagnosis
Medications & Supplements
From 
Infectious Disease Resources
Featured Centers
Health Solutions From Our Sponsors
Health Solutions From Our Sponsors

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.
https://reference.medscape.com/drug/chloramphenicol-iv-chloromycetin-342554#0
https://www.uptodate.com/contents/chloramphenicol-drug-information
https://www.accessdata.fda.gov/drugsatfda_docs/label/2005/050155s039lbl.pdf
https://www.ncbi.nlm.nih.gov/books/NBK448133/