Introduction
Pen G is an antibiotic used to treat a variety of bacterial infections. It is effective in infections of the throat, ear, nasal sinuses, respiratory tract, skin and soft tissue, and sexually transmitted diseases like Syphilis.
Pen G is also used to prevent some infections such as Rheumatic fever and infection of the heart valves (bacterial endocarditis) in people with pre-existing heart disease. It is a penicillin-type of antibiotic, which mainly fights and stops the growth of the gram-positive type of bacteria. This tablet may be swallowed with or without food, but it should be used regularly at evenly spaced intervals as per the schedule prescribed by your doctor.
Do not skip any doses and finish the full course of treatment even if you feel better. Stopping the medicine too early may lead to the infection returning or worsening. The total duration of treatment and precise dosage will be decided by your doctor, depending on the type of infection that you have and how well you respond to the medication.
Before taking this medicine, inform your doctor if you are allergic to penicillin or any penicillin-type of medicine. Rash, vomiting, allergic reactions, nausea and diarrhea may be seen as side effects in some patients. These are temporary and usually resolve quickly. Consult your doctor if any of these side effects persist or if your condition worsens. This medicine is generally regarded as safe to use during pregnancy if used under a doctor's supervision.
Uses of Pen G
- Bacterial infections
- Syphilis
- Prevention of rheumatic fever
Side effects of Pen G
Common
- Rash
- Vomiting
- Allergic reaction
- Nausea
- Diarrhea
How to use Pen G
Take this medicine in the dose and duration as advised by your doctor. Swallow it as a whole. Do not chew, crush or break it. Pen G may be taken with or without food, but it is better to take it at a fixed time.
How Pen G works
Pen G is an antibiotic. It kills bacteria by preventing them from forming the bacterial protective covering (cell wall) which is needed for them to survive.
Indication
Meningitis, Anthrax, Community-acquired pneumonia, Bacterial endocarditis, Septicemia, Diphtheria, Syphilis, Cellulitis, Infective endocarditis, Gonorrhea, Aspiration pneumonia, Lung abscess, Septic Arthritis, Gangrene, Meningococcal meningitis, Pneumococcal meningitis, Botulism
Administration
IM Administration
Do not inject near artery or nerve (may result in permanent neurologic damage)
Neonates, infants, small children: Midlateral aspect of thigh preferable
Older children and adults: Deep IM injection in upper outer quadrant of buttock
Because of high concentration of suspended matter, needle may be blocked if injection is not made at slow, steady rate
Reconstitution: Loosen the powd, then, hold the vial horizontally and rotate it while slowly directing the stream of diluent against the wall of the vial. Shake the vial vigorously after all the diluent has been added. Depending on the route of admin, reconstitute w/ sterile water for inj, NaCl 0.9% inj or dextrose 5% inj.
Adult Dose
Adult: IV Bacterial endocarditis W/ aminoglycoside: 1.2 g 4 hrly. Intrapartum prophylaxis against group B streptococcal infection Initial: 3 g, then 1.5 g 4 hrly until delivery.
Meningococcal meningitis; Pneumococcal meningitis 2.4 g 4 hrly. Up to 18 g/day in meningococcal meningitis.
IV/IM Susceptible infections 0.6-4.8 g/day in divided doses.
Child Dose
Infant & Children: Bacterial Infection
IV, IM 100,000–250,000 U/kg/day q4–6h
Max daily dose is 24 million U.
Renal Dose
Renal impairment: Dosing interval should be no more frequent than every 8-10 hr.
Contraindication
Hypersensitivity to penicillins.
Mode of Action
Benzylpenicillin has a bactericidal action against gram-positive bacteria, gram-negative cocci, some other gram-negative bacteria, spirochetes and actinomycetes. It inhibits final cross-linking stage of peptidoglycan production through binding and inactivation of transpeptidases on the inner surface of the bacterial cell membrane thus inhibiting bacterial cell wall synthesis. It is inhibited by penicillinase and other beta-lactamases.
Precaution
Very high doses in poor renal function (risk of neurotoxicity) or heart failure. Avoid contact, skin sensitization may occur. Monitor serum potassium concentration, renal and haematological status. Spirochete infections particularly syphilis; suprainfection with penicillin-resistant organisms with prolonged use; avoid intrathecal route.
Lactation: Excreted into breast milk, caution advised
Side Effect
Hypersensitivity reactions including uticaria; fever; joint pains; rashes; angioedema; serum sickness-like reactions; haemolytic anaemia; interstitial nephritis; neutropenia; thrombocytopenia; CNS toxicity including convulsions; diarrhoea; antibiotic-associated colitis.
Potentially Fatal: Anaphylaxis.
Pregnancy Category Note
Pregnancy Category: B
Lactation: Excreted into breast milk, caution advised
Interaction
Probenecid
Increases and prolongs serum penicillin levels.
Tetracycline
May antagonize the bactericidal effect of penicillin.