Penicillin V potassium (Penicillin VK) is an antibiotic used to treat several types of infections throughout the body in adults and children. It's available as tablets and suspension that are taken by mouth. The dosage depends on the type of infection you have and how severe it is, but the medication is typically taken every 6 to 12 hours. Side effects include nausea, diarrhea, and vomiting.
Certain types of streptococcal infections, such as upper respiratory tract infections, strep throat, scarlet fever, erysipelas (a type of skin infection)
Pneumococcal respiratory tract infections
Staphylococcal skin infections
Prevention of rheumatic fever or chorea (long-term problems from strep infection)
Prevention of heart valve infections in certain people with heart problems
Penicillin V potassium (Penicillin VK) is a type of penicillin antibiotic. It kills bacteria by preventing them from making an additional covering around themselves for protection.
Source: DailyMed
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.
Stop taking this medicine and get emergency help immediately if any of the following effects occur:
Less common
Fast or irregular breathing
joint pain
lightheadedness or fainting (sudden)
puffiness or swelling around the face
red, scaly skin
shortness of breath
Check with your doctor immediately if any of the following side effects occur:
Rare
Abdominal or stomach cramps and pain (severe)
abdominal tenderness
convulsions (seizures)
decreased amount of urine
diarrhea (watery and severe), which may also be bloody
mental depression
pain at place of injection
sore throat and fever
unusual bleeding or bruising
yellow eyes or skin
Rare
For penicillin G procaine only
Agitation or combativeness
confusion
fear of impending death
feeling, hearing, or seeing things that are not real
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:
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.
Works well to treat many different bacterial infections
Can use for adults and children
Can be taken with or without food
Available as a tablet and suspension
Can cause stomach side effects like nausea, vomiting, and diarrhea
Might not be able to take this medication if you've had a severe allergy to penicillin
Not recommended for treating a cold or the flu because these are viral infections
Needs to be taken every 6 to 8 hours
Take penicillin V potassium (Penicillin VK) exactly as prescribed. Make sure to finish your treatment course, even if you're feeling better. Stopping the medication earlier than prescribed can make your infection come back and become harder to treat.
Swallow the penicillin V potassium (Penicillin VK) oral tablets whole. If you're having trouble swallowing them, ask your prescriber about switching you to the suspension (liquid).
You can take penicillin V potassium (Penicillin VK) with or without food. But nausea, vomiting, and diarrhea are common with antibiotics, so taking it with food can help lessen or prevent these side effects.
Don't drink alcohol while taking penicillin V potassium (Penicillin VK) because it could raise your risk for stomach side effects (e.g., nausea, vomiting, diarrhea). Drinking alcohol can also make it harder for you to recover from your infection since alcohol can weaken your immune system.
Get medical attention as soon as possible if you have a rash, itchy skin, difficulty breathing, or swelling in your face or mouth. These could be signs of a severe allergic reaction.
Ask your healthcare professional (HCP) whether it's safe and appropriate for you to take a probiotic to help lessen the risk of a rare, but more serious form of diarrhea caused by a Clostridium difficile (C. diff) bacterial infection. If your HCP says you can, make sure to separate the probiotic from penicillin V potassium (Penicillin VK) by at least 2 hours to prevent the antibiotic from killing the "good" bacteria in the probiotic.
Get medical help as soon as possible if you develop watery or bloody diarrhea, fever, fatigue, or stomach cramps anytime during treatment or after stopping penicillin V potassium (Penicillin VK). These could be signs of C. difficile-related diarrhea, which needs to be treated right away.
Penicillin V potassium (Penicillin VK) is generally safe to take while pregnant or breastfeeding. But to be safe, it's always best to let your primary care provider know that you're pregnant or breastfeeding before starting penicillin V potassium (Penicillin VK) so they can go over the risks and benefits of the medication with you.
More tips for penicillin V potassium (Penicillin VK) oral suspension:
Make sure you know which strength of the penicillin V potassium (Penicillin VK) oral suspension you have to avoid giving the wrong dose. The suspension comes as 125 mg/5 mL and 250 mg/5 mL.
Shake the bottle well before measuring out the dose. Make sure to only use an oral dosing syringe from the pharmacy to measure out your dose. Don't use household spoons because they aren't accurate and might cause you to take the wrong dose.
Store the penicillin V potassium (Penicillin VK) suspension in the refrigerator. After 14 days, throw away the bottle, even if there's still some medication left. Your pharmacist typically writes this date on the bottle to help remind you when to throw it away.
Penicillin V potassium (Penicillin VK) 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.
Risk factors: History of allergy to penicillin or cephalosporin antibiotics
Severe allergic reactions to penicillin V potassium (Penicillin VK) are possible, including life-threatening reactions like facial swelling and anaphylaxis (e.g., closing of the throat). Let your healthcare professional (HCP) know if you have an allergy to antibiotics. If you notice hives, rash, red skin, swelling of the lips or tongue, or difficulty breathing after taking penicillin V potassium (Penicillin VK), get medical help right away.
Diarrhea is a common side effect of taking antibiotics, including penicillin V potassium (Penicillin VK). But rarely, people have reported infectious diarrhea, which can be life-threatening. This happens because antibiotics change the balance of gut bacteria in your stomach and intestines. Sometimes, the "bad" bacteria takes over and causes serious infections. Get medical help right away if you experience symptoms of infectious diarrhea, including fast heart rate, foul-smelling diarrhea, fever, nausea, bloody stools, and stomach cramps.
Your HCP will make sure that you're taking penicillin V potassium (Penicillin VK) for the appropriate infection and amount of time. Using penicillin V potassium (Penicillin VK) for any shorter or longer periods of time or taking the antibiotic for other illnesses can raise your risk for developing infections caused by drug-resistant bacteria. This raises your risk for severe and life-threatening infections that might be difficult to treat.
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 any of these medicines, 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 medicines in this class 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.
Severe allergy to other penicillins or beta-lactam antibiotics
Certain types of streptococcal infections, such as upper respiratory tract infections, strep throat, scarlet fever, erysipelas (a type of skin infection)
Pneumococcal respiratory tract infections
Staphylococcal skin infections
Prevention of rheumatic fever or chorea (long-term problems from strep infection)
Prevention of heart valve infections in certain people with heart problems
Skin infections
Bone infections
Urinary tract infections (UTIs)
Reproductive system infections
Upper respiratory tract infections (ear, nose, and throat infections)
Lower respiratory tract infections (e.g., pneumonia, bronchitis)
Skin infections (e.g., cellulitis)
Helicobacter pylori infection (adults only)
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