Penicillin V Potassium

About Penicillin V Potassium

Penicillin V kills bacteria by stopping them from building their cell walls; its potassium salt resists stomach acid better than penicillin G and is taken by mouth. The label covers mild to moderately severe infections caused by bacteria sensitive to penicillin G: streptococcal infections without bacteremia, such as strep throat and other upper airway infections, scarlet fever and mild erysipelas (a skin infection); pneumococcal respiratory infections, including middle ear infections; mild skin and soft tissue infections caused by staphylococci sensitive to penicillin G; and Vincent’s infection of the gums and throat. For adults and children aged 12 and over, strep infections take 125 to 250 mg every 6 to 8 hours for ten days, and the others 250 to 500 mg every 6 to 8 hours (every 6 hours for pneumococcal infections, until the fever has been gone for at least two days). The label says severe pneumonia, empyema, bacteremia, pericarditis, meningitis and arthritis should not be treated with it during the acute stage.

There is no boxed warning. Anyone who has had an allergic reaction to any penicillin must not take it: serious and occasionally fatal reactions, including anaphylaxis, have occurred, and some people allergic to penicillin have reacted severely to cephalosporins. A rash, hives, wheezing, swelling of the throat, tongue or lips, or trouble breathing or swallowing needs a call to the doctor at once or emergency care. Nausea, vomiting, stomach upset, diarrhea and black hairy tongue are the most common side effects, and watery or bloody diarrhea can be Clostridioides difficile infection, even two or more months after the last dose. The label urges caution with asthma or significant allergies, and says not to rely on it by mouth in severe illness or with nausea or vomiting.

Strep infections need at least ten days of treatment, and the label calls for a culture afterward to confirm the bacteria are gone. To keep rheumatic fever or chorea from returning, it is taken at 125 to 250 mg twice a day on a continuing basis. The label also describes a regimen that the American Heart Association and the American Dental Association suggested for preventing heart valve infection (bacterial endocarditis) in some people with congenital or valve heart disease who have dental procedures or upper airway surgery. It notes that no controlled studies of its effectiveness were done, says it should not be used in people at particularly high risk, such as those with artificial heart valves, and tells the physician or dentist choosing an antibiotic for this purpose to read the associations’ full joint statement.

Taking Penicillin V Potassium

How to take it

At about the same times each day, usually every 6 to 8 hours, or twice a day for rheumatic fever prevention. It may be taken with meals, though the label notes blood levels are slightly higher on an empty stomach. Shake the liquid well before each dose, and finish the full course even if you feel better.

If you miss a dose

Take it as soon as you remember, unless it is almost time for the next dose; then skip the missed dose and carry on as usual. Do not take a double dose.

Storage

Tablets at room temperature, tightly closed, away from heat and moisture. Keep the mixed liquid in the refrigerator, do not freeze it, and throw away what is left after 14 days. Keep both out of reach of children.

Interactions to know about

The label lists no specific drug interactions. Tell the prescriber about every medicine and supplement you take, any past allergic reaction (the label asks specifically about penicillins and cephalosporins), asthma, hay fever, kidney disease, and current nausea or vomiting, and call about watery or bloody diarrhea.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Penicillin V Potassium differs from pharmacy to pharmacy

Penicillin V is an old generic made by several companies, so a quote for the tablets is mostly the pharmacy’s dispensing fee and markup, and a pharmacy that keeps it on a flat-price generic list can quote less than one that prices each fill separately.

Fewer companies make the oral solution. It comes in 100 and 200 mL bottles that the pharmacy mixes when it fills the prescription and that keep 14 days in the refrigerator, so the bottle size and the number of bottles a course needs shape the quote, and a pharmacy that does not stock the strength prescribed may need to order it.

Ways to pay less for Penicillin V Potassium without insurance

• Ask whether penicillin V is on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• For a child’s liquid, confirm the pharmacy stocks the strength prescribed and ask how many bottles the full course needs, so the quote covers all of it.
• If a child can swallow tablets, ask the prescriber whether tablets would suit instead of the liquid.
• For long-term prevention after rheumatic fever, ask the prescriber about a ninety-day supply.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Penicillin V Potassium

1. 1.Should I take it with meals or on an empty stomach?
2. 2.How do I store my child’s liquid, and when do I throw it away?
3. 3.Which rash, swelling or breathing problem means I should stop it and get help?
4. 4.Will I need a throat culture after I finish the course?

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