Penicillin is an antibiotic used to treat and prevent a
wide variety of bacterial infections. It works by stopping the growth of
bacteria.
This antibiotic treats and prevents only bacterial
infections. It will not work for virus infections (such as the common cold,
flu). Using any antibiotic when it is not needed can cause it to not work
for future infections.
Take this medication by mouth as directed by your
doctor. This medication may be taken with or without food. However,
penicillin is best absorbed when taken on an empty stomach (1 hour before
or 2 hours after meals).
The dosage is based on your medical condition and
response to treatment.
For the best effect, take this antibiotic at evenly
spaced times. To help you remember, take this medication at the same
time(s) every day.
Continue to take this medication until the full
prescribed amount is finished, even if symptoms disappear after a few days.
Stopping the medication too early may result in a return of the
infection.
Tell your doctor if your condition lasts or gets
worse.
Upset stomach, nausea, vomiting, diarrhea, and mouth
sores may occur. If any of these effects last or get worse, tell your
doctor or pharmacist promptly.
Although this effect is uncommon, you may develop a
black, "hairy" tongue while taking this medication. This effect is harmless
and usually goes away after treatment. Maintain good oral hygiene, and
brush your tongue with a soft toothbrush twice a day. Consult your doctor
or pharmacist for more information.
Remember that this medication has been prescribed
because your doctor has judged that the benefit to you is greater than the
risk of side effects. Many people using this medication do not have serious
side effects.
Tell your doctor right away if you have any serious side
effects, including:
- unusual tiredness
- joint/muscle pain
- easy bruising/bleeding
This medication may rarely cause a severe intestinal
condition due to a bacteria called C. difficile. This condition may occur
during treatment or weeks to months after treatment has stopped. Tell your
doctor right away if you develop:
- diarrhea that doesn't stop
- abdominal or stomach pain/cramping
- blood/mucus in your stool
If you have these symptoms, do not use anti-diarrhea or
opioid products because they may make symptoms worse.
Use of this medication for prolonged or repeated periods
may result in oral thrush or a new vaginal yeast infection (oral or vaginal
fungal infection). Contact your doctor if you notice white patches in your
mouth, a change in vaginal discharge or other new symptoms.
A very serious allergic reaction to this drug is rare.
However, get medical help right away if you notice any symptoms of a
serious allergic reaction, including:
- rash
- itching/swelling (especially of the face/tongue/throat)
- new fever
- severe dizziness
- trouble breathing
This is not a complete list of possible side effects. If
you notice other effects not listed above, contact your doctor or
pharmacist.
In the US - Call your doctor for medical advice about side effects.
You may report side effects to FDA at 1-800-FDA-1088 or at
www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about
side effects. You may report side effects to Health Canada at
1-866-234-2345.
Before taking penicillin, tell your doctor or pharmacist
if you are allergic to it; or to other antibiotics including
penicillin-type medications (such as amoxicillin, ampicillin) or
cephalosporins (such as cephalexin, cefuroxime); or if you have any other
allergies. This product may contain inactive ingredients, which can cause
allergic reactions or other problems. Talk to your pharmacist for more
details.
Before using this medication, tell your doctor or
pharmacist your medical history, especially of:
Penicillin may cause live bacterial vaccines (such as
typhoid vaccine) to not work well. Tell your health care professional that
you are using penicillin before having any
immunizations/vaccinations.
During pregnancy, this medication should be used only
when clearly needed. Discuss the risks and benefits with your
doctor.
This drug passes into breast milk. Consult your doctor
before breastfeeding.
Drug interactions may change how your medications work
or increase your risk for serious side effects. This document does not
contain all possible drug interactions. Keep a list of all the products you
use (including prescription/nonprescription drugs and herbal products) and
share it with your doctor and pharmacist. Do not start, stop, or change the
dosage of any medicines without your doctor's approval.
Some products that may interact with this drug
are:
- methotrexate
- khat
- guar gum
This medication may interfere with certain lab tests
(such as certain diabetic urine tests), possibly causing false test
results. Make sure lab personnel and all your doctors know you use this
drug.
If someone has overdosed and has serious symptoms such
as passing out or trouble breathing, call 911. Otherwise, call a poison
control center right away. US residents can call 1-800-222-1222. Canada
residents can call 1-844-764-7669. Symptoms of overdose may include:
diarrhea that doesn't stop, severe vomiting.
Do not share this medication with others.
This medication has been prescribed for your current
condition only. Do not use it later for another infection unless your
doctor tells you to.
With long term treatment, lab and/or medical tests (such
as kidney function, complete blood counts) should be done while you are
taking this medication. Keep all medical and lab appointments. Consult your
doctor for more details.
If you miss a dose, take it as soon as you remember. If
it is near the time of the next dose, skip the missed dose. Take your next
dose at the regular time. Do not double the dose to catch
up.
Store at room temperature away from light and moisture.
Do not store in the bathroom. Keep all medications away from children and
pets.
Do not flush medications down the toilet or pour them
into a drain unless instructed to do so. Properly discard this product when
it is expired or no longer needed. Consult your pharmacist or local waste
disposal company.
