Tablet
Cytapen 250 mg Tablet
Generic: Phenoxymethylpenicillin (Penicillin V)
Manufacturer: Edruc Ltd.
Therapeutic class: Natural Penicillin Antibiotic
What is Cytapen?
Cytapen 250 mg tablet from Edruc Ltd. contains Phenoxymethylpenicillin (Penicillin V) — phenoxymethylpenicillin, also known as penicillin V — one of the oldest and most trusted oral antibiotics in the world. Doctors prescribe it for streptococcal throat infections, mild skin and gum infections, and as long-term protection against recurrent rheumatic fever, a disease that still damages children's hearts in Bangladesh. It is a prescription-only medicine.
Phenoxymethylpenicillin (Penicillin V) kills bacteria by stopping them from cross-linking the layers of their cell wall. The wall collapses and the bacterium bursts. Unlike older injectable penicillins, it resists stomach acid so it can be swallowed — but food greatly reduces its absorption, which is why it is taken on an empty stomach.
Indications
Cytapen is prescribed for infections caused by penicillin-sensitive bacteria, including:
- Streptococcal throat infections: pharyngitis, tonsillitis and scarlet fever
- Mild skin and soft-tissue infections such as erysipelas
- Gum and dental infections, often alongside other treatment
- Prevention of recurrent rheumatic fever — taken daily, sometimes for years, to protect the heart
- Prevention of pneumococcal infection in people without a spleen or with sickle cell disease
Penicillin V remains the first-choice drug worldwide for strep throat because resistance of streptococci to penicillin is still rare. Use it only for the condition your doctor prescribed it for.
Dosage & Administration
Take Cytapen exactly as prescribed. Typical adult doses of Phenoxymethylpenicillin (Penicillin V):
- Most infections: 250–500 mg every 6 hours
- Streptococcal throat infection: 250–500 mg every 6–8 hours for a full 10 days
- Rheumatic fever prevention: 250 mg twice daily, continued long term as the cardiologist advises
Take each dose on an empty stomach — 1 hour before or 2 hours after food — because food sharply reduces absorption. Space doses evenly through the day. Children's doses are based on age and weight and must be set by a doctor. In significant kidney disease, high doses may need adjustment.
Side Effects
Cytapen has decades of safety experience. Possible side effects include:
- Nausea, vomiting, loose stools or stomach discomfort
- Skin rash, itching or hives
- Sore mouth or tongue, and oral or vaginal thrush with longer courses
The most important rare risk is a severe allergic reaction (anaphylaxis): sudden breathing difficulty, wheezing, swelling of the face, lips or throat, widespread hives, dizziness or collapse — usually within an hour of a dose. This is a medical emergency: stop the medicine and go to hospital immediately. Persistent watery or bloody diarrhoea, unusual bruising or yellow eyes also need prompt medical review.
Precautions & Warnings
Cytapen is a prescription-only antibiotic. Bangladesh's antibiotic-resistance crisis is fuelled by pharmacy-counter sales and abandoned courses, so take it only on a doctor's advice and complete the entire course. For strep throat this means all 10 days — a shortened course can fail to clear the streptococcus and leaves children at risk of rheumatic fever and lifelong heart-valve damage.
- Tell your doctor about any previous reaction to penicillin or any antibiotic before the first dose
- Mention asthma, allergic disorders, kidney disease or a history of colitis
- If you are on long-term Cytapen for rheumatic fever prevention, do not stop without consulting your cardiologist
Drug Interactions
Phenoxymethylpenicillin (Penicillin V) interacts with relatively few medicines, but tell your doctor and pharmacist everything you take. Important ones:
- Probenecid (gout medicine): raises penicillin blood levels — sometimes used deliberately, but only under medical guidance
- Methotrexate: penicillins can reduce its removal from the body and increase toxicity
- Tetracycline-class antibiotics may blunt penicillin's bacteria-killing action — avoid combining unless your doctor directs
- Warfarin: INR can occasionally shift during antibiotic courses; monitoring is wise
- Live oral typhoid vaccine becomes ineffective during antibiotic treatment — keep the recommended gap
Severe vomiting or diarrhoea from any cause can reduce absorption of both Cytapen and oral contraceptive pills; use back-up contraception if this happens.
Contraindications
Do not take Cytapen if you:
- Are allergic to phenoxymethylpenicillin, amoxicillin, ampicillin or any other penicillin
- Have ever had anaphylaxis, throat swelling, severe hives or collapse after any beta-lactam antibiotic (penicillins or cephalosporins)
Tell your doctor before starting if you have severe kidney impairment, a history of severe allergy or asthma, or previous antibiotic-associated colitis — extra caution or an alternative drug may be needed. A history of a vague "reaction" in childhood should be described in detail to your doctor rather than simply avoiding penicillin forever: many such patients are not truly allergic, and penicillin is often the best, narrowest-spectrum choice.
Pregnancy & Lactation
Pregnancy: Penicillins, including Phenoxymethylpenicillin (Penicillin V), have one of the longest safety records of any antibiotic family in pregnancy, with no evidence of harm to the unborn baby across decades of use. Cytapen is therefore often a preferred antibiotic for pregnant women — but it should still be taken only when prescribed by a doctor who knows about the pregnancy.
Breastfeeding: Only trace amounts of Phenoxymethylpenicillin (Penicillin V) pass into breast milk, and breastfeeding can normally continue during treatment. Rarely the infant may develop loose stools, rash or oral thrush; tell your doctor if this occurs. There is a theoretical chance of sensitising an allergic-prone baby, so always confirm with your doctor first.
Storage Conditions
Store Cytapen tablets below 30°C in a dry place, away from direct sunlight and household humidity — avoid bathroom shelves in Bangladesh's damp climate. Keep the strips in the original carton, and keep all medicines locked away or well out of children's reach and sight.
- Reconstituted Phenoxymethylpenicillin (Penicillin V) syrup should be kept in the refrigerator (2–8°C), shaken before each dose, and any remainder discarded after the period stated on the label — usually 7 to 14 days
- Never use Cytapen after its expiry date; expired penicillin loses potency
- Return unused antibiotics to a pharmacy rather than discarding them into drains or bins
Frequently Asked Questions
Why must I take Cytapen on an empty stomach?
<p>Food in the stomach binds and degrades phenoxymethylpenicillin and sharply reduces how much reaches your blood — sometimes leaving too little to kill the bacteria reliably. Taking Cytapen 1 hour before or 2 hours after meals ensures full absorption and full effect. If you keep forgetting, link the doses to fixed daily moments, such as just after waking and before bedtime. Only if nausea is severe should you discuss taking it differently with your doctor.</p>
My child's throat pain is gone — why must they finish all 10 days of Cytapen?
<p>Because the goal is not just comfort but completely clearing the streptococcus germ. If treatment stops early, surviving bacteria can trigger rheumatic fever two to three weeks later — an immune reaction that scars heart valves for life and still affects many children in Bangladesh. Stopping early also breeds antibiotic-resistant bacteria. The 10-day course of Cytapen is the proven length that prevents both. Give every dose, even when your child seems perfectly well by day three.</p>
What allergy warning signs should I watch for while taking Cytapen?
<p>Watch for sudden itching, widespread hives, swelling of the lips, face, tongue or throat, wheezing or difficulty breathing, severe dizziness or collapse — usually within minutes to an hour of a dose. These signal anaphylaxis: stop Cytapen and rush to the nearest hospital or emergency room immediately. A mild, delayed skin rash should also be reported to your doctor before the next dose. If you have ever reacted to any penicillin before, tell your doctor before starting — do not test it yourself.</p>
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