cefazolin
Cefazolin (Ancef) is a first-generation cephalosporin antibiotic that treats many types of bacterial infections and prevents infections from surgery. It fights infections by killing bacteria. This medication can be used in adults and children over 1 month of age. Cefazolin (Ancef) is only available as an injection that's given through the veins (intravenously or IV) or into the muscle (intramuscularly or IM). Side effects aren't common, but you might not be able to take cefazolin (Ancef) if you have an allergy to other antibiotics, such as penicillins and other cephalosporins like cephalexin.
What is Cefazolin (Ancef)?
What is Cefazolin (Ancef) used for?
- Respiratory tract infections
- Urinary tract infections (UTIs)
- Skin infections
- Liver and gallbladder infections
- Bone and joint infections
- Genital infections
- Bloodstream infections
- Heart infections
- Prevention of infection from surgery
How Cefazolin (Ancef) works
Cefazolin (Ancef) is a cephalosporin antibiotic. It kills bacteria by preventing them from making their own protective covering.
Drug facts
Side effects of Cefazolin (Ancef)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
- Side effects aren't common. See Other.
Less Common Side Effects
- Diarrhea
- Nausea or vomiting
- Stomach cramps
- Low appetite
- Itching
- Rash
- Fungal growth in the mouth (oral thrush)
- Abnormal liver lab test results
- Kidney injury or abnormal kidney lab test results
Cefazolin (Ancef) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Severe allergic reaction: itching, hives, swelling in your face or throat, chest tightness, trouble breathing
- C. difficile infection: loose, watery stools (diarrhea), severe stomach pain, fever, nausea
The following Cefazolin (Ancef) side effects have also been reported
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
Incidence not known
Abdominal or stomach cramps or tenderness
back, leg, or stomach pains
black, tarry stools
bleeding gums
blistering, peeling, or loosening of the skin
blood in the urine or stools
bloody or cloudy urine
chills
clay-colored stools
cloudy urine
coughing up blood
dark urine
decrease in urine output or decrease in urine-concentrating ability
decreased frequency or amount of urine
diarrhea, watery and severe, which may also be bloody
difficult or painful urination
difficulty with breathing or swallowing
dizziness
excessive muscle tone
fast heartbeat
feeling of discomfort
general body swelling
general tiredness and weakness
headache
increased blood pressure
increased menstrual flow or vaginal bleeding
increased thirst
inflammation of the joints
itching of the vagina or genital area
joint or muscle pain
light-colored stools
loss of appetite
lower back or side pain
muscle aches or stiffness
muscle tension or tightness
nausea or vomiting
nosebleeds
pain during sexual intercourse
pain, warmth, or burning in the fingers, toes, and legs
pale skin
paralysis
pinpoint red spots on the skin
problems with vision or hearing
prolonged bleeding from cuts
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
rash
red irritated eyes
red or black, tarry stools
red or dark brown urine
red skin lesions, often with a purple center
red, irritated eyes
restlessness
seizures
skin rash
sores, ulcers, or white spots on the lips or in the mouth
stomach cramps
sudden decrease in the amount of urine
swelling of the face, fingers, or lower legs
swollen lymph glands
swollen or painful glands
thick, white vaginal discharge with no odor or with a mild odor
tightness in the chest
trouble sitting still
troubled breathing
unpleasant breath odor
unusual bleeding or bruising
unusual tiredness or weakness
unusual weight loss
upper right abdominal pain
vomiting
vomiting of blood
yellowing of the eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
hives or welts
redness of the skin
sore mouth or tongue
white patches in the mouth, tongue, or throat
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Pros and cons of Cefazolin (Ancef)
Pros
- Treats many types of bacterial infections
- Helps prevent infections from happening if you get it right before surgery
- Generally has few side effects
- Safe to use during pregnancy as long as the potential benefits outweigh the risks
Cons
- Only available as an injection, so it's usually given in the hospital or provider's office
- Not recommended to be used for viral infections (e.g., the common cold)
- Can be troublesome to take, especially if you need to take it every 6 to 8 hours (3 to 4 times a day)
- Can leave a metallic or sour taste in the mouth
Pharmacist tips for Cefazolin (Ancef)
- Tell your provider or get medical help right away if you have a rash, itchy skin, trouble breathing, or swelling in your face or mouth. These could be signs that you're having an allergic reaction to cefazolin (Ancef).
- You might have diarrhea or stomach upset when you're taking cefazolin (Ancef). These side effects should get better soon after you finish your treatment course. Tell your provider if the diarrhea gets worse or if you start having loose, watery stools or stomach cramps. These can be signs of a serious type of infectious diarrhea.
Tips for using cefazolin (Ancef) at home (if instructed by your provider)
- In certain situations, your provider might allow you to take cefazolin (Ancef) on your own at home. Speak with your provider to learn the proper techniques for using this medication safely.
- Cefazolin (Ancef) comes in two forms that are used for injection: vials of powder that need to be mixed with a liquid (diluent) and premixed bags of liquid solution. Carefully follow your provider's instructions on how to store the form of the antibiotic you have, how to prepare cefazolin (Ancef) for injection, and how to inject the medication. Ask your provider or pharmacist if you have any questions.
- Look at the solution closely before injecting the medication. The color of the cefazolin (Ancef) solution should be pale yellow to yellow. Don't use the solution if you see any particles (solid chunks) or abnormal color; call your pharmacy about what to do next.
- Make sure to completely finish your treatment with cefazolin (Ancef) as instructed by your provider, even if you start to feel better. Your infection can come back and be harder to treat if you stop taking the medication too early.
Common questions about Cefazolin (Ancef)
Cefazolin (Ancef) is a cephalosporin, which is a class of antibiotics that are like cousins to penicillin. Their chemical structures have some similarities, and they both kill bacteria by preventing them from making their own protective covering. Cephalosporins tend to have the ability to fight against a broader range of bacteria than standard penicillins.
You might not be able to take cefazolin (Ancef) if you're allergic to penicillin or other cephalosporin antibiotics. Cephalosporins like cefazolin (Ancef) are structurally similar to penicillins, so there's a risk that you could have a reaction to cefazolin (Ancef) if you've had an allergic reaction to penicillin in the past. Be sure your healthcare team is aware if you've had any kind of allergic reaction to penicillin or other cephalosporin antibiotic before, especially if you've had trouble breathing or swelling in your face or neck. Your provider will weigh the risks and benefits of using cefazolin (Ancef) to make sure it's safe for you. Your provider might decide to use a different antibiotic to be safe.
No, cefazolin (Ancef) isn't a sulfa drug. This means that you can take this antibiotic if you're allergic to any sulfa drugs, like Bactrim or Septra (sulfamethoxazole / trimethoprim).
Cephalosporins are grouped into five different generations based on which types of bacteria they cover. Cefazolin (Ancef) is a first-generation cephalosporin. First-generation antibiotics are able to fight against a handful of Gram-positive bacteria like Staphylococcus aureus (S. aureus) and the streptococci species. They can't fight against very many Gram-negative bacteria, mainly Escherichia coli (E. coli) and Proteus mirabilis.
Cephalexin (Keflex) and cefazolin (Ancef) aren't the same medication. Both are cephalosporin antibiotics that have similar chemical structures and work the same way to kill bacteria. But they're given differently: cefazolin (Ancef) is only available as an injection that's typically given by a healthcare provider, whereas cephalexin (Keflex) is an antibiotic that's taken by mouth and conveniently at home.
No, cefazolin (Ancef) won't treat bacterial infections that are due to MRSA, which is the abbreviation for methicillin-resistant Staphylococcus aureus. MRSA is considered a drug-resistant bacteria and the infections it causes are typically hard to treat. Many antibiotics, including cephalosporins like cefazolin (Ancef), don't work against MRSA well. This drug-resistant bacteria is treatable with only a few specific antibiotics.
After you take a single dose of cefazolin (Ancef), most of the medication will leave your body within 12 hours if you have good kidney function. This time frame is based on the half-life of cefazolin (Ancef), a measure of how long a medication stays in the body. Keep in mind that most people need to take cefazolin (Ancef) many times a day, so the medication will most likely stay in your system longer if you've taken multiple doses in a row. In addition, since your kidneys help get rid of cefazolin (Ancef) from the body, the medication might stay in your system longer if your kidneys don't work well. That's why some people with kidney problems will need to take a lower dose or take the medication less often to prevent it from building up in the body and causing more side effects.
No, cefazolin (Ancef) is only available in forms that are meant to be given as an injection. If you can take medications by mouth, your provider might prescribe cephalexin (Keflex), which is a similar cephalosporin antibiotic that comes in tablets, capsules, and also as a liquid suspension. Keep in mind that the antibiotic and route of administration (e.g., by mouth, by injection) your provider chooses will depend on what infection you have and how severe it is.
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Risks and warnings for Cefazolin (Ancef)
Cefazolin (Ancef) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Allergic reaction
- Risk factors: History of allergy to penicillin or other cephalosporin antibiotics
Let your provider know if you've had an allergic reaction from taking penicillin-type or cephalosporin antibiotics in the past because you might be at risk for an allergic reaction from cefazolin (Ancef) too. Cefazolin (Ancef) might not be the safest option for you and your provider might prescribe another antibiotic. Get medical attention right away if you experience an allergic reaction, such as trouble breathing or swelling in your face and neck, at anytime during your treatment with cefazolin (Ancef).
Diarrhea caused by C. difficile infection
- Risk factors: Taking cefazolin (Ancef) for a long time | Recent use of other antibiotics | Stomach problems
In rare cases, taking antibiotics like cefazolin (Ancef) can raise your risk of getting a serious bacterial infection that causes severe diarrhea. This infection is caused by the Clostridioides difficile (or C. diff) bacteria.
C. diff diarrhea can cause foul-smelling diarrhea, watery stools, very frequent bowel movements, stomach pain, and fever. This diarrhea can lead to life-threatening dehydration (low fluids in the body). Symptoms can start anytime after you start your antibiotic, but it can also happen up to 2 months later. Call your provider or get medical help right away if you experience symptoms of C. diff diarrhea because you should get treated as soon as possible.
Development of drug-resistant bacteria
- Risk factors: Taking cefazolin (Ancef) for a non-bacterial infection | Taking cefazolin (Ancef) for too long | Taking cefazolin (Ancef) to prevent a bacterial infection
You should only take cefazolin (Ancef) to treat bacterial infections. Using antibiotics like cefazolin (Ancef) when they aren't necessary or for too long can lead to infections caused by drug-resistant bacteria. These new or worsened infections from drug-resistant bacteria can be much harder to treat. Let your provider know if you notice symptoms of a new infection or if the original symptoms don't get better.
Requires dose adjustment in people with kidney problems
- Risk factors: History of kidney problems | Older adult
Your body removes cefazolin (Ancef) through the kidneys. When your kidneys aren't working well, cefazolin (Ancef) can build up in your body. Too much cefazolin (Ancef) in the body can cause more side effects and other problems, such as seizures. Make sure your provider is aware of any kidney problems you have. Your provider will adjust the dose of cefazolin (Ancef) for you based on your blood test results that give information about your kidney health. Dose adjustments help lower your risk for side effects if you have kidney problems.
Cefazolin (Ancef) dosage
Typical dosage for Cefazolin (Ancef)
Cefazolin (Ancef) is usually given as an IV infusion in a hospital by your healthcare team or at home by a visiting nurse. It can alternatively be given as an injection into one of your large muscles.
Your healthcare provider will make sure you get cefazolin (Ancef) at the correct dose and time. Your dose might differ if you have kidney problems.
Adults: Your dose will depend on what type of infection you have and how severe it is.
- Mild infections: The typical dose is 250 mg to 500 mg given every 8 hours.
- Urinary tract infections: The typical dose is 1,000 mg given every 12 hours.
- Pneumococcal pneumonia: The typical dose is 500 mg given every 12 hours.
- Moderate-to-severe infections: The typical dose is 500 mg to 1,000 mg given every 6 to 8 hours.
- Severe, life-threatening infections (e.g., heart infections, bloodstream infections): The typical dose is 1,000 mg to 1,500 mg given every 6 hours.
- Prevention of infection from surgery: The typical dose is 1,000 mg given 30 minutes to 1 hour before the start of surgery. For certain procedures, your provider might continue giving cefazolin (Ancef) during surgery and even for up to a day after your procedure.
Children: The dose will depend on how much your child weighs and how severe your child's infection is.
- Most mild-to-moderate infections: The typical total daily dose is 25 mg to 50 mg per kg of body weight. This daily dose is usually split up into 3 or 4 equal doses throughout the day.
- Severe infections: The total daily dose can go up to 100 mg per kg of body weight. This daily dose is usually split up into 3 or 4 equal doses throughout the day.
Interactions between Cefazolin (Ancef) and other drugs
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Cholera Vaccine, Live
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Cefazolin (Ancef) contraindications
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Cefazolin (Ancef) will not be safe for you to take.
- Allergy to cephalosporin antibiotics
What are alternatives to Cefazolin (Ancef)?
Cefazolin (Ancef) images
