Medically reviewed by Drugs.com. Last updated on Jan 3, 2022.
The Omnicef brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
- Powder for Suspension
Therapeutic Class: Antibiotic
Pharmacologic Class: 3rd Generation Cephalosporin
Uses for Omnicef
Cefdinir is used to treat bacterial infections in many different parts of the body. It belongs to the class of medicines known as cephalosporin antibiotics. It works by killing bacteria or preventing their growth. However, this medicine will not work for colds, flu, or other virus infections.
This medicine is available only with your doctor's prescription.
Before using Omnicef
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of cefdinir in children. However, safety and efficacy have not been established in infants younger than 6 months of age.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of cefdinir in the elderly. However, elderly patients are more likely to have age-related kidney problems, which may require caution and an adjustment in the dose for patients receiving cefdinir.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
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 taking 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
- Ethinyl Estradiol
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.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Colitis (inflammation in gut), history of or
- Diarrhea, severe, history of—Use with caution. May make these conditions worse.
- Diabetes—The oral liquid form of this medicine contains sucrose (table sugar), which can make this condition worse.
- Kidney disease—Use with caution. Effects may be increased because of slower removal of the medicine from the body.
Proper use of Omnicef
Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
You may take this medicine with or without food.
Shake the oral liquid well before each use. Measure the medicine with a marked measuring spoon, oral syringe, or medicine cup. The average household teaspoon may not hold the right amount of liquid.
If you are taking aluminum or magnesium-containing antacids, iron supplements, or multivitamins, do not take them at the same time that you take this medicine. It is best to take these medicines at least 2 hours before or after taking cefdinir. These medicines may keep cefdinir from working properly.
Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (capsules or suspension):
- For infections:
- Adults and teenagers—300 milligrams (mg) every twelve hours or 600 mg once a day, taken for 5 to 10 days.
- Infants and children 6 months up to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 7 milligrams (mg) per kilogram (kg) of body weight every twelve hours or 14 milligrams (mg) per kilogram (kg) of body weight per day, taken for 5 to 10 days. However, the dose is usually not more than 600 mg per day.
- Infants up to 6 months of age—Use and dose must be determined by your doctor.
- For infections:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Throw away any unused medicine after 10 days.
Precautions while using Omnicef
If your symptoms do not improve within a few days, or if they become worse, check with your doctor.
Cefdinir may cause diarrhea, and in some cases it can be severe. Do not take any medicine or give medicine to your child to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea continues or gets worse, check with your doctor.
Before you or your child have any medical tests, tell the medical doctor in charge that you are using this medicine. The results of some tests may be affected by this medicine.
Omnicef side effects
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 immediately if any of the following side effects occur:
- Black, tarry stools
- chest pain
- painful or difficult urination
- shortness of breath
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- swollen glands
- unusual bleeding or bruising
- unusual tiredness or weakness
Incidence not known
- Abdominal or stomach cramps or tenderness
- back, leg, or stomach pains
- bleeding gums
- blistering, peeling, or loosening of the skin
- blood in the urine or stools
- bloody nose
- bloody or cloudy urine
- bloody, black, or tarry stools
- blue lips, fingernails, or skin
- chest pain or discomfort
- clay-colored stools
- cold, clammy skin
- coughing or vomiting blood
- cracks in the skin
- dark-colored urine
- diarrhea, watery and severe, which may also be bloody
- difficult or troubled breathing
- difficulty with breathing or swallowing
- dilated neck veins
- extreme fatigue
- fast heartbeat
- fast, weak pulse
- feeling of discomfort
- general body swelling
- general tiredness and weakness
- heavier menstrual periods
- high fever
- increased thirst
- inflammation of the joints
- irregular breathing
- irregular heartbeat
- irregular, fast or slow, or shallow breathing
- joint or muscle pain
- light-colored stools
- loss of appetite
- loss of consciousness
- loss of heat from the body
- muscle aches
- muscle cramps or spasms
- muscle pain or stiffness
- nausea or vomiting
- noisy breathing
- pain in the ankles or knees
- pain or discomfort in the arms, jaw, back, or neck
- painful, red lumps under the skin, mostly on the legs
- pale skin
- persistent bleeding or oozing from puncture sites, mouth, or nose
- pinpoint red spots on the skin
- problems with bleeding or clotting
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- red skin lesions, often with a purple center
- red, irritated eyes
- red, swollen skin
- scaly skin
- severe stomach pain
- slow or irregular breathing
- sudden decrease in the amount of urine
- swelling of the face, fingers, feet, or lower legs
- swollen lymph glands
- tightness in the chest
- unpleasant breath odor
- unusual weight loss
- upper right abdominal or stomach pain
- vomiting of blood
- weight gain
- yellow 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:
- Itching of the vagina or genital area
- pain during sexual intercourse
- thick, white vaginal discharge with no odor or with a mild odor
- vaginal yeast infection
- Acid or sour stomach
- dry mouth
- excess air or gas in the stomach or intestines
- full feeling
- increase in body movements
- increased clear or white vaginal discharge
- lack or loss of strength
- passing gas
- rash with flat lesions or small raised lesions on the skin
- sleepiness or unusual drowsiness
- soreness or redness around the fingernails and toenails
- stomach discomfort, upset, or pain
- unable to sleep
Incidence not known
- Burning, dry, or itching eyes
- discharge, excessive tearing
- redness, pain, or swelling of the eye, eyelid, or inner lining of the eyelid
- swelling or inflammation of the mouth
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.
Frequently asked questions
More about Omnicef (cefdinir)
- Side effects
- Drug interactions
- Dosage information
- During pregnancy or Breastfeeding
- Reviews (48)
- Drug images
- Generic availability
- En español
- Drug class: third generation cephalosporins
- Other brands
- Omnicef Omni-Pac
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.