How many days after antibiotics is strep not contagious

Q: How long after taking antibiotics for strep throat Am I contagious?

Youre usually no longer infectious 24 hours after starting a course of antibiotics, but this time period can sometimes vary. For example, the antibiotics may take longer to work if your body takes longer to absorb them, or if youre taking other medicine that interacts with the antibiotics.

US Pharm. 2022;47(5):15-16.

Table of Contents Show

Bacterial Throat Infection
Testing Confirms Presence of Bacteria
Most Infections Respond Quickly to Antibiotics
Stopping the Spread of Strep Infection
Recurring infections
How do you know when strep is no longer contagious?
How long after taking antibiotics for strep throat Am I contagious?

Bacterial Throat Infection

Pharyngitis is an inflammation of the pharynx, the area in the back of the throat. This inflammation causes the symptom of a sore throat. Although most infectious causes of sore throat are due to viruses, about 5% to 10% of pharyngitis cases result from a bacterial infection. Strep throat describes these throat infections since the bacteria most often responsible for bacterial pharyngitis are a strain of Streptococcus bacteria. Strep throat is most common in children aged 3 to 15 years, but it can occur at any age. Strep throat spreads easily and quickly from person to person in close-contact settings, such as schools, households, or day-care centers.

Testing Confirms Presence of Bacteria

Classic symptoms of strep throat include a painful sore throat, difficulty swallowing, fever, swollen neck glands, nausea, and headache. Upon examination, the throat appears red, often with white or yellow dots or streaks, tiny red dots on the upper palate, and swollen tonsils. Sore throats accompanied by cold or flu-like symptoms, such as nasal congestion and cough, are typically caused by a virus, and antibiotics are not effective to kill viruses. To avoid the unnecessary use of antibiotics and development of resistance, the diagnosis of a bacterial infection is essential before prescribing antibiotics. Since symptoms alone cannot definitively diagnose strep throat caused by bacteria, a rapid strep test detects the presence of a bacterial infection using a swab of the throat, followed by a culture if the rapid test is negative.

Most Infections Respond Quickly to Antibiotics

Antibiotics are the appropriate treatment for strep throat since they stop the further spread of bacteria, reduce the risk of spreading the infection to other areas of the body, and help prevent serious complications. There are many antibiotics used in the treatment of strep throat. Most commonly used are penicillin or amoxicillin (Amoxil). Other antibiotics used to treat are azithromycin (Zithromax, Z-Pak), cephalosporins, clarithromycin, and clindamycin. Side effects from antibiotics are generally mild and include stomachache, nausea, vomiting, and diarrhea. Factors to consider in the choice of antibiotic include the sensitivity of the bacteria to the antibiotic, patient allergies, dosing, taste, and cost. Seek emergency care immediately if wheezing, trouble breathing, rash, or fast heartbeat develops after antibiotic use. These symptoms can indicate an allergic reaction.

Acetaminophen or ibuprofen is appropriate to treat a fever, but aspirin should not be used in children and teens due to the risk of Reye’s syndrome. Nonprescription lozenges and sprays may help soothe a sore throat, and saltwater gargles are effective in reducing sore throat pain.

Although unusual, an untreated strep throat can lead to a sinus or ear infection, abscess of the tonsils, scarlet fever, or more serious complications, such as kidney disease (glomerulonephritis) or heart disease (rheumatic fever). After 24 hours of antibiotic therapy, patients with strep throat are no longer considered contagious and can return to school or work if they have no fever. Most cases of strep throat respond quickly to antibiotic therapy, but patients must finish the entire course of medication to avoid the bacteria from returning. If a strep throat returns after appropriate treatment, the source of Streptococcus may be a close contact (who may or may not have symptoms) or an ineffective antibiotic.

Stopping the Spread of Strep Infection

Since Streptococcus bacteria are highly contagious through saliva and nasal secretions, prevention of the spread of strep is similar to measures used against viral cold or influenza. This includes hand washing and covering the mouth and nose when coughing or sneezing. Patients should not return to school, day care, or work until they are no longer contagious and have no fever, usually 24 to 48 hours after beginning antibiotics. Streptococcus bacteria can also remain alive on objects such as a toothbrush for several days, so replacing a toothbrush after 24 to 48 hours of antibiotic therapy and thoroughly cleaning orthodontic retainers every day can prevent patients from reinfecting themselves.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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Strep throat is an infection of the throat and tonsils. It’s caused by a type of bacteria called group A Streptococcus (GAS).

It’s a highly contagious bacterial infection, and it can make your throat very sore and scratchy.

Read on to learn more about how strep throat is spread, how long it’s contagious, and what you can do to reduce your risk for the condition.

GAS bacteria can spread from person to person through contact with respiratory droplets from a person with strep throat. These droplets may be spread when a person with strep throat coughs or sneezes.

If you’re exposed to these droplets and then touch your mouth, nose, or eyes, you may contract strep throat. You may also get the infection if you:

share food or a beverage with someone who has strep throat
come into contact with a contaminated object, such as a faucet or doorknob

If you’ve been infected with strep, it can take two to five days for you to develop symptoms.

If you’ve been exposed to the bacteria, you can be contagious a few days before symptoms start.

If you’re treated with antibiotics, you’ll remain contagious until you’ve been on antibiotics for at least 24 hours. If you don’t seek treatment, you’ll remain contagious for 2 to 3 weeks after contracting the infection.

Strep throat is most common in school-age children. According to the Centers for Disease Control and Prevention (CDC), up to 30 percent of children with a sore throat have strep throat. Only 10 percent of adults with a sore throat have strep throat.

Adults who are frequently around school-age children have a higher risk of getting strep throat. Since strep throat is very contagious, being in crowded places, such as schools or daycare centers, can increase your risk of becoming sick.

You can get strep throat at any time of the year, but it’s generally more prevalent in the late fall or early spring.

Recurring infections

Even if you’ve had strep throat before, you can get it again. Some children have recurring strep throat, contracting the disease multiple times in a year.

In the case of recurring infections, your doctor may recommend tonsil removal to help decrease the frequency of strep throat infections. This procedure is called a tonsillectomy. However, you can still get strep throat even after your tonsils have been removed.

If you suspect that you have strep throat, you should see your doctor in order to get tested and begin treatment. Penicillin or amoxicillin are typically used to treat strep throat. If you’re allergic to penicillin, other antibiotics can be used.

Antibiotics may help you feel better faster. They can also shorten the amount of time that you’re contagious.

Most people are no longer contagious after they’ve taken antibiotics for at least 24 hours. Be sure to finish your entire course of antibiotics, though (unless your doctor tells you otherwise).

In addition to antibiotics, your doctor may recommend over-the-counter (OTC) medications such as ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) to help with your symptoms.

If you receive antibiotic treatment for your strep throat, your illness may only last for one to three days.

If left untreated, recovery will take longer, and your risk for developing complications will increase. Additionally, without treatment, you can still be contagious for several weeks, even after you stop feeling sick.

Follow these tips to help prevent the spread of strep throat:

Clean your hands properly and regularly. Be sure to use an alcohol-based hand sanitizer or soap and warm water.
Clean surfaces in your house if you, or someone in your house, has strep throat. Bacteria can survive for short periods of time on household items, such as doorknobs and tabletops.
If you live with or care for someone with strep throat, be sure to wash your hands frequently. Also avoid touching your face, nose, and mouth.
Avoid contact with anyone who has strep throat until they’ve been on antibiotics for at least 24 hours.
Don’t share food, drinks, or eating utensils with others. Additionally, avoid sharing personal items, such as toothbrushes.
If you have strep, be sure to cover your mouth when you cough or sneeze. Carry disposable tissues with you. If you don’t have a tissue, sneeze into the crook of your elbow instead of into your hand.
If you have strep throat, be aware that you’re contagious as long as you have symptoms, and you should stay home from work or school. Once you start taking antibiotics, you should stay home until you’ve been on them for at least 24 hours.

How do you know when strep is no longer contagious?

People with strep throat should stay home from work, school, or daycare until they no longer have a fever and have taken antibiotics for at least 12 hours. This will help prevent spreading the bacteria to others. Wash your hands often to prevent the spread of germs that cause strep throat and other infections.

How long after taking antibiotics for strep throat Am I contagious?

You're usually no longer infectious 24 hours after starting a course of antibiotics, but this time period can sometimes vary. For example, the antibiotics may take longer to work if your body takes longer to absorb them, or if you're taking other medicine that interacts with the antibiotics.