(Also known as Penicillin V)
Phenoxymethylpenicillin is the active ingredient of Betapen (Nappi Code:
780081-013 & 751111-014), Len V.K. (Nappi Code: 736635-017 &
830089-004), Spec-Pen-VK 250 (Nappi Code: 700174- 006).
Penicillins are antibiotics that are derived from a mold. It is used to treat
infections caused by harmful bacteria. In South Africa phenoxymethylpenicillin
is registered for the treatment of bacterial infections caused by susceptible
organisms including tonsillitis, pharyngitis and for the prevention of rheumatic
fever after a streptococcal infection.
Should you develop a skin rash whilst being treated with this medication, you
should notify your doctor to rule out the possibility of allergy.
A penicillin allergy may lead to fever, swelling of the mouth and tongue,
itching and associated breathing difficulties.
Phenoxymethylpenicillin is only effective against bacterial infections and is
useless for treating viral infections such as cold or flu.
Antibiotic resistance occurs when a bacterium develops the ability to defend
itself against the effect of an antibiotic. It occurs frequently with this
antibiotic. The most common causes for resistance is patients not completing
prescribed antibiotic courses allowing the bacteria to recover from treatment,
and the use of antibiotics for non-bacterial infections such as cold and
This antibiotic is best absorbed if taken on an empty stomach. To prevent a
reduction of absorption into the body, it should be taken at least 60 minutes
before or 3 hours after a meal.
How does phenoxymethylpenicillin work?
functions by changing the structure of the bacterial cell wall, allowing fluid
to penetrate into the cell. As a result the bacterial cell literally
Drug schedule: schedule 4
phenoxymethylpenicillin is available as tablets and suspension.
it do? Phenoxymethylpenicillin has an antibiotic effect.
Dependence risk: low
available as a generic? yes
Is Phenoxymethylpenicillin available on
prescription only? yes
Onset of effect: within 4 hours
Duration of action: up
to 12 hours
Dietary advice: This drug should best be taken on an empty
Stopping this medicine: complete the full course as prescribed
by your doctor, even if you feel better within a few days. Premature
discontinuation may cause symptoms to recur, or cause bacterial
Prolonged use: phenoxymethylpenicillin is generally given
as short courses only. Prolonged use may increase the risk of a
Consult your doctor before using this
- you have a known allergy to penicillin or cephalosporin
- you have kidney or liver disease
Pregnancy: avoid. It is unknown how this medication may affect
your baby. Consult your doctor before using this drug, or if you are planning to
Breastfeeding: avoid. This medication is passed through
breast milk and may affect your baby adversely. Consult your doctor before
Porphyria: this medication is safe to use.
children: this medication is safe for use in children at the recommended
The elderly: no special precautions need to be
Driving and hazardous work: no special precautions need to be
Alcohol: no special precautions need to be taken.
Possible side effects
Consult your doctor
Only if severe
In all cases
loss of consciousness
||increased risk of skin rash|
||reduces the efficacy of antibiotic|
||possible reduced contraceptive efficacy. Another form of contraceptive
||increased risk of antibiotic toxicity|
||possible reduced antibiotic efficacy|
||increased risk of warfarin toxicity|
Consult your doctor before using this
drug if you have a known allergy to penicillin or cephalosporin antibiotics, or
if you have kidney or liver disease.
A small overdose is no cause for concern. In
case of intentional large overdose seek emergency medical attention.
Adults: 1000mg - 2000mg daily in
divided doses. Doses of up to 6000mg daily have been used.
This material is not intended to substitute medical advice, but
is for informational purposes only. Please consult a physician for specific
treatment and recommendations.