Unasyn

Common Uses

Unasyn is an injectable medication used to treat a variety of infections caused by bacteria. It is most commonly prescribed for:

• Skin infections: This includes infections of the skin and the underlying tissues.
• Intra-abdominal infections: These are infections that occur inside the abdominal cavity.
• Gynecological infections: This includes infections involving the female reproductive organs.

How It Works

This medication is a combination of two drugs: ampicillin and sulbactam. Ampicillin is a penicillin-type antibiotic that works by stopping the growth of bacteria. Sulbactam is a beta-lactamase inhibitor that helps prevent certain bacteria from breaking down the ampicillin, allowing the antibiotic to work more effectively against resistant strains.

Important Considerations

Unasyn is only effective against bacterial infections. It will not work for viral infections, such as the common cold or influenza. Using antibiotics when they are not needed increases the risk of developing an infection later that resists antibiotic treatment.

How Unasyn Fights Infection

Unasyn contains two active ingredients that work together to treat bacterial infections: ampicillin and sulbactam.

Ampicillin

Ampicillin is a penicillin-type antibiotic. It works by interfering with the ability of bacteria to form stable cell walls. Because the cell wall is essential for the bacteria to survive and multiply, this interference causes the bacteria to die.

Sulbactam

Sulbactam is a medication known as a beta-lactamase inhibitor. Many types of bacteria have developed a defense mechanism where they produce enzymes called beta-lactamases. These enzymes can break down and deactivate ampicillin before it has a chance to work. Sulbactam works by blocking these enzymes, which protects the ampicillin and allows it to effectively attack the bacteria.

Combined Action

By combining these two medicines, Unasyn can treat a wider variety of infections, including those caused by bacteria that have become resistant to ampicillin alone. This medication is only effective against bacterial infections and will not work for viral infections, such as the common cold or the flu.

Common Side Effects

Common side effects of Unasyn may include:

• Pain, redness, or swelling at the injection site
• Diarrhea
• Nausea or vomiting
• Rash or itching
• Headache
• White patches in the mouth or changes in vaginal discharge, which may indicate a yeast infection

Serious Side Effects

Seek medical attention immediately if you experience any of the following serious symptoms:

• Signs of a severe allergic reaction, such as hives, difficulty breathing, or swelling of the face, lips, or throat
• Severe stomach pain and watery or bloody diarrhea, which may occur during treatment or several months after the last dose
• Severe skin reactions, including fever, sore throat, and a red or purple rash that blisters or peels
• Yellowing of the skin or the whites of the eyes (jaundice)
• Dark-colored urine or pale stools
• Unusual bruising or bleeding
• Seizures, particularly in individuals with kidney disease or those receiving high doses

Allergic Reactions

Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients receiving penicillin therapy. These reactions are more likely to occur in individuals with a history of sensitivity to multiple allergens. Before starting treatment, it is important to consider any previous history of reactions to penicillins, cephalosporins, or other beta-lactam antibacterial drugs.

Severe Skin Reactions

Unasyn can cause severe cutaneous adverse reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS). If a severe skin rash or reaction occurs, treatment must be discontinued immediately and appropriate therapy started.

Liver Function

Hepatic dysfunction, including hepatitis and cholestatic jaundice, has been associated with the use of this medication. It is contraindicated in patients with a prior history of liver problems specifically related to the use of ampicillin and sulbactam. Liver function may need to be monitored during prolonged therapy.

Diarrhea and Colitis

Clostridioides difficile-associated diarrhea (CDAD) has been reported with nearly all antibacterial agents, including Unasyn. This condition can range in severity from mild diarrhea to fatal inflammation of the colon. It can occur during treatment or more than two months after the antibiotic course has finished.

Other Precautions

• Mononucleosis: A high percentage of patients with mononucleosis develop a skin rash when taking ampicillin-class antibiotics. This medication should generally be avoided in patients with viral mononucleosis.
• Superinfection: The use of this antibiotic may result in the overgrowth of non-susceptible organisms, including fungi. If superinfection occurs, appropriate measures should be taken.
• Kidney Impairment: Because ampicillin and sulbactam are primarily excreted by the kidneys, patients with impaired kidney function may require dosage adjustments.

Pregnancy

There are no adequate and well-controlled studies of Unasyn in pregnant women. Research in animals using high doses has not shown evidence of impaired fertility or harm to the fetus, but animal studies do not always predict how a human will respond. This medication is known to cross the placenta. Because of the limited data in humans, healthcare providers usually only prescribe this medication during pregnancy if the potential benefits outweigh the potential risks.

Breastfeeding

Both ampicillin and sulbactam are excreted in human breast milk in low concentrations. While many healthcare providers consider this compatible with breastfeeding, there is a small risk that the nursing infant could develop side effects such as diarrhea, fungal infections (thrush), or a skin rash. If you are breastfeeding, discuss the potential risks and benefits with your doctor to determine the best course of action for you and your child.

Available Forms

Unasyn is supplied in several formats for administration by a healthcare professional:

• Powder for Injection: This form is provided in vials and must be mixed with a sterile liquid before it is administered.
• Pharmacy Bulk Package: This is a larger container of sterile powder used in clinical settings to prepare multiple doses for intravenous infusion.
• Premixed Solution: This version is supplied as a frozen, ready-to-use liquid in plastic containers that is thawed before being infused into a vein.

Depending on the specific form and the needs of the patient, Unasyn may be administered as an injection into a large muscle or as an infusion into a vein.

FDA Approval and Indications

Unasyn was approved by the U.S. Food and Drug Administration (FDA) for the treatment of specific infections caused by susceptible bacteria. It is a combination of ampicillin, a penicillin-class antibiotic, and sulbactam, a beta-lactamase inhibitor. Approved uses include:

• Skin and skin structure infections
• Intra-abdominal infections
• Gynecological infections

Safety and Regulatory Status

The FDA has not issued a boxed warning for Unasyn. However, the medication is subject to standard regulatory monitoring for safety. Key safety warnings included in the FDA-approved labeling involve:

• Hypersensitivity: Serious and occasionally fatal allergic reactions (anaphylaxis) have been reported in patients on penicillin therapy.
• Clostridioides difficile-associated diarrhea (CDAD): Like many antibiotics, Unasyn can cause CDAD, which may range in severity from mild diarrhea to life-threatening inflammation of the colon.
• Hepatotoxicity: Cases of liver dysfunction have been reported with the use of this combination.

Unasyn is approved for use in both adult and pediatric patients (one year of age and older) for specific indications. It is administered via injection into a muscle or vein by a healthcare provider.

Cost Considerations

Unasyn is an injectable antibiotic that is typically administered by a healthcare professional in a hospital or clinical setting. Because it is not usually purchased at a retail pharmacy, the cost is often bundled into the overall charges for medical services rather than being a standalone prescription price.

Generic Availability

A generic version of Unasyn, known as ampicillin and sulbactam, is available. Generic medications are required to have the same active ingredients and effectiveness as the brand-name version but are generally available at a lower cost.

Insurance and Billing

Several factors can influence the final out-of-pocket cost for this medication:

• Insurance Coverage: Most health insurance plans, including Medicare and Medicaid, cover ampicillin and sulbactam when it is medically necessary. The specific cost to the patient will depend on the plan's deductibles, copayments, or coinsurance requirements.
• Setting of Care: The price may differ depending on whether the medication is received during an inpatient hospital stay, at an outpatient clinic, or through a home infusion service.
• Dosage and Duration: The total cost is affected by the specific dose prescribed by the doctor and the length of the treatment course.

Patients are encouraged to contact their insurance provider or the billing department of their healthcare facility for specific pricing information and to determine their expected financial responsibility.