Purbac

 Purbac

 Purbac contains two active ingredients that work in combination to enhance the antibacterial effect:

• Sulfamethoxazole – a sulfonamide group substance that inhibits folic acid synthesis in bacterial cells, disrupting microbial reproduction.

• Trimethoprim – enhances the effect of sulfamethoxazole by blocking the next stage of folic acid synthesis. As a result, bacteria lose their ability to grow and divide, leading to their destruction.

This combination makes Purbac effective against a wide range of bacterial infections, including strains resistant to other antibiotics.

Purbac is available in several forms to allow patients to take it in the most convenient way. Physicians prescribe the form based on the patient’s age, condition, and infection severity. For example, children find the suspension easier to take, while severe infections in hospitals may require injections.

• Tablets – the primary option for adults and adolescents. A standard tablet contains 400 mg of sulfamethoxazole and 80 mg of trimethoprim, while the Purbac Double Strength version contains 800 mg/160 mg. The tablets are film-coated, making them easier to swallow and gentler on the stomach.

• Oral suspension – a liquid form, primarily prescribed for children. Each 5 ml of suspension contains 200 mg of sulfamethoxazole and 40 mg of trimethoprim. The bottle must be shaken before use to evenly distribute the active ingredients. Thanks to its sweet taste, it is easier for young children to take.

• Injection solution – used for severe infections requiring rapid achievement of high blood concentration. Each 1 ml of solution contains 80 mg of sulfamethoxazole and 16 mg of trimethoprim. Injections are typically administered in hospitals under medical supervision.

The form of the drug affects not only convenience but also the speed of action. Tablets and suspensions begin working within 1–4 hours, while injections act almost immediately. The doctor selects the optimal form depending on the situation.

Purbac is prescribed for various bacterial infections sensitive to its active components. It effectively eliminates pathogens by disrupting their ability to reproduce. Physicians use it to treat infections of the respiratory tract, urinary system, gastrointestinal tract, skin, and soft tissues.

• Urinary tract infections (UTIs) (cystitis, pyelonephritis) – fights bacteria causing bladder and kidney inflammation in both acute and chronic cases.

• Respiratory tract infections (bronchitis, pneumonia) – used to treat bacterial infections of the bronchi and lungs, especially if the pathogens are susceptible to sulfamethoxazole and trimethoprim.

• Gastrointestinal infections (shigellosis, salmonellosis) – helps with intestinal infections that cause diarrhea, fever, and dehydration. Purbac inhibits the growth of pathogenic bacteria, easing the disease course.

• Skin and soft tissue infections (erysipelas, abscesses) – prescribed for bacterial skin inflammations, pustular lesions, and infected wounds.

• Toxoplasmosis – a parasitic infection, particularly dangerous for pregnant women and immunocompromised individuals. The drug is used as part of combination therapy.

• Pneumocystis pneumonia – prescribed for immunocompromised patients (e.g., those with HIV) to reduce the risk of severe lung inflammation caused by Pneumocystis jirovecii.

It is important to note that Purbac is only effective against bacterial infections. It is not used to treat viral diseases such as influenza or acute respiratory viral infections. Self-prescribing antibiotics can lead to bacterial resistance, so treatment should always be conducted under a doctor’s supervision.

Purbac is taken orally with a sufficient amount of water. Food intake does not affect its effectiveness; however, if you have a sensitive stomach, it is recommended to take the tablets after meals to reduce nausea and gastric irritation.

Dosage for adults and adolescents (from 12 years old)

• Standard regimen – 1–2 tablets (400 mg/80 mg) every 12 hours.

• For severe infections – the dose may be increased to 2 tablets twice daily (800 mg/160 mg).

• Course duration – usually 5 to 14 days, depending on the type and severity of the infection.

Dosage for children

The dosage for children depends on age and the dosage form:

• 6 to 12 years – 1 tablet every 12 hours. If the child cannot swallow the tablet, the suspension can be used: 10 ml (2 teaspoons) twice daily.

• 2 to 6 years – 5 ml (1 teaspoon) of suspension every 12 hours.

• Under 2 years – the drug is not prescribed for children under 2 months due to the risk of side effects.

Use in special cases

In some situations, Purbac is prescribed according to a specific regimen:

• Prophylaxis of Pneumocystis pneumonia – 1 tablet (400 mg/80 mg) once daily.

• Elderly patients – the physician may adjust the dose since kidney function decreases with age, which affects drug elimination. It is also important to monitor potassium levels, as Purbac may cause hyperkalemia.

Duration of treatment

• Mild to moderate infections – 5 to 7 days.

• Severe infections (pneumonia, complicated UTIs) – treatment may last up to 14 days.

• If symptoms persist or worsen, consult a doctor to adjust the treatment.

Important!

To ensure effective treatment, follow these recommendations:

• Do not skip doses – this can reduce the effectiveness of therapy and contribute to bacterial resistance.

• If you miss a dose, take it as soon as possible. If the next dose is soon, do not double it — simply continue according to the schedule.

• Drink plenty of water throughout the day – this helps protect the kidneys and reduce the risk of side effects.

Before starting treatment, it is important to ensure that the patient does not have conditions that contraindicate the use of Purbac. Certain diseases and individual characteristics may enhance side effects or make the medication unsafe.

• Hypersensitivity to sulfonamides or trimethoprim – If a patient has previously experienced an allergic reaction to these substances, taking Purbac again may cause rashes, angioedema, or anaphylactic shock.

• Severe liver or kidney dysfunction – In cases of significant impairment of these organs, the drug is not properly excreted, leading to accumulation and increased toxicity risk.

• Glucose-6-phosphate dehydrogenase (G6PD) deficiency – A rare hereditary condition where Purbac may cause hemolysis (destruction of red blood cells), leading to anemia and other complications.

• Pregnancy (especially in the first trimester and before childbirth) – The drug may interfere with fetal nervous system development, increasing the risk of congenital defects. In later stages, it can cause neonatal jaundice.

• Children under 2 months – In infants, enzyme systems are not yet fully developed, making metabolism of the drug unsafe.

Before prescribing Purbac, the physician assesses the patient’s overall condition and potential risks. If contraindications exist, alternative antibiotics that do not cause complications are selected.

If unusual symptoms, worsening health, or allergic reactions appear during treatment, the drug should be discontinued immediately, and a doctor should be consulted.

Purbac requires caution in prescribing, especially for patients with specific conditions or a predisposition to side effects. The doctor must consider possible risks and adjust the dosage or prescribe additional tests if necessary.

• Patients with a history of allergic reactions – If a person has had allergies to medications or foods before, there is a risk of a reaction to Purbac. Possible symptoms include rashes, itching, swelling, or even anaphylaxis.

• Folic acid deficiency – Long-term use of the drug can reduce folate levels in the body. This is especially important for elderly patients, pregnant women, and individuals with chronic blood disorders. In some cases, doctors may prescribe additional folic acid supplements.

• Monitoring kidney and liver function during prolonged treatment – Since the drug is primarily excreted through the kidneys, it may accumulate in patients with kidney impairment. Patients with chronic kidney and liver diseases should regularly undergo laboratory tests.

• Risk of superinfections – Prolonged antibiotic use can lead to the growth of resistant bacteria or fungi, requiring a change in treatment. If symptoms persist or new complaints appear, a follow-up medical consultation is necessary.

• Avoid UV exposure – Purbac increases skin sensitivity to sunlight (photosensitization), raising the risk of sunburn and irritation. During treatment, it is recommended to minimize sun exposure, wear protective clothing, and use sunscreen.

Additional monitoring is required for elderly patients, immunocompromised individuals, and those taking other drugs that interact with Purbac. If unusual symptoms or worsening health occur, consult a doctor to adjust the therapy.

Purbac may interact with other medications, enhancing or reducing their effects. This is particularly important for patients taking multiple drugs simultaneously, as improper combinations may lead to adverse effects.

Medications that may cause serious interactions with Purbac:

• Warfarin – Purbac enhances the anticoagulant effect of warfarin, increasing the risk of bleeding. Blood clotting levels (INR) should be monitored, and dosage adjustments may be necessary.

• Methotrexate – Increases methotrexate toxicity, which can lead to bone marrow suppression, anemia, leukopenia, and other hematological complications. Regular blood tests are required during co-administration.

• Phenytoin – Increases phenytoin concentration in the blood, raising the risk of side effects such as drowsiness, dizziness, ataxia (coordination disorders), and cognitive impairments.

• Diuretics (thiazide diuretics) – Co-administration increases the risk of thrombocytopenia, particularly in elderly patients, leading to bleeding tendencies, bruising, and coagulation disorders.

• Cyclosporine – Purbac may lower cyclosporine levels in the blood, reducing its immunosuppressive effect and increasing the risk of transplant rejection. Additionally, both drugs are nephrotoxic, placing a strain on the kidneys.

• Potassium supplements and ACE inhibitors (enalapril, lisinopril, captopril) – Co-administration with Purbac can lead to hyperkalemia (elevated potassium levels), increasing the risk of cardiac arrhythmias and heart problems.

• Oral hypoglycemic agents (glibenclamide, glipizide, gliclazide) – Purbac enhances their effect, which may cause a sharp drop in blood sugar levels, leading to hypoglycemia (dizziness, sweating, fainting). Diabetic patients should monitor glucose levels during treatment.

• Antiepileptic drugs (lamotrigine, carbamazepine) – May increase side effects and toxicity due to slower metabolism.

• Digoxin (cardiotonic agent) – Purbac can raise digoxin levels in the blood, particularly in elderly patients, increasing the risk of arrhythmias and toxicity.

Additional interactions:

• Hormonal contraceptives – Antibiotics, including Purbac, may reduce the effectiveness of oral contraceptives, so additional contraceptive methods are recommended.

• Vitamin C and hexamethylenetetramine (urotropin) – May increase the risk of crystal formation in the urine (crystalluria), particularly at high doses. This can cause urinary tract irritation and complications.

• Indomethacin and other NSAIDs – May increase Purbac concentrations in the blood, raising the risk of side effects.

Some drugs may weaken Purbac's action, reducing its effectiveness, so it is important to inform the doctor about all medications being taken, including over-the-counter and herbal products.

If unusual symptoms, worsening health, or side effects occur while taking Purbac, consult a doctor for possible therapy adjustments.

Purbac is not recommended during pregnancy and breastfeeding, as its active ingredients may affect fetal development and the health of a newborn.

Pregnancy

Purbac is contraindicated during pregnancy, especially in the first trimester and shortly before childbirth. This is due to the risk of fetal development abnormalities. The drug may interfere with folic acid metabolism, increasing the likelihood of congenital neural tube defects.

Additionally, late-term use of Purbac may lead to neonatal jaundice, a condition where bilirubin accumulates in the blood and may cause brain damage.

If antibacterial therapy is required during pregnancy, the doctor will select safer alternatives.

Breastfeeding

Purbac passes into breast milk and may cause jaundice, anemia, and allergic reactions in infants. Therefore, it is not recommended for use during breastfeeding. If treatment is necessary, the mother should temporarily discontinue lactation and switch the baby to formula feeding.

Effect on Fertility

Currently, there is insufficient data on the effect of Purbac on reproductive function in men and women. However, since the drug can disrupt folate metabolism, it theoretically may affect spermatogenesis and ovulation.

Purbac may cause dizziness, weakness, and reduced concentration, especially in the first days of use.

If these symptoms occur, it is advisable to avoid driving, operating machinery, or performing tasks requiring high attention levels. In patients with significant side effects, driving may be unsafe.

If severe fatigue, coordination issues, or confusion occur, the patient should inform their doctor.

Like any antibiotic, Purbac may cause adverse reactions affecting various body systems.

Gastrointestinal System

• Nausea, vomiting, diarrhea – the most common side effects. Taking the drug after meals and drinking plenty of water can help prevent them.

• Abdominal pain, indigestion – possible with prolonged use.

• Loss of appetite – occurs less frequently but may result from the drug’s effect on the digestive system.

Allergic Reactions

• Skin rash, itching, urticaria – the most common allergic manifestations.

• Photosensitivity – increased skin sensitivity to sunlight, leading to sunburn and irritation.

• Angioedema, anaphylactic shock – rare but serious complications requiring immediate medical attention.

Blood System

• Leukopenia (reduced white blood cell count) – may weaken the immune system and increase susceptibility to infections.

• Thrombocytopenia (reduced platelet count) – can lead to gum bleeding, bruising, and increased bleeding risk.

• Hemolytic anemia – especially in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Nervous System

• Headache, dizziness – may occur in the first days of treatment and usually subside as the body adapts.

• Drowsiness or, conversely, anxiety – rare but possible in sensitive individuals.

Kidneys and Urinary System

• Crystalluria – formation of crystals in urine, which may irritate the urinary tract and cause discomfort.

• Elevated potassium levels (hyperkalemia) – may lead to heart rhythm disturbances, weakness, and numbness in the extremities.

Other Side Effects

• Chills, fever – may occur as a reaction to the drug.

• Muscle and joint pain – rare, but may resemble flu-like symptoms.

Taking Purbac in doses exceeding the recommended amount may lead to overdose, which presents with various symptoms depending on the drug quantity and individual characteristics.

Main Symptoms of Overdose

• Nausea, vomiting, diarrhea – due to irritation of the stomach and intestinal lining.

• Dizziness, weakness, confusion – associated with electrolyte imbalance and toxic effects on the nervous system.

• Bone marrow suppression – possible with significant overdose, leading to decreased white blood cell, platelet, and red blood cell counts, causing anemia, weakened immunity, and clotting disorders.

• Crystalluria and kidney damage – high doses of Purbac may cause crystal formation in the urine, increasing the risk of urinary tract irritation and kidney failure.

Overdose Treatment

• Gastric lavage – effective if the drug was taken recently, helping to reduce absorption.

• Forced diuresis – the patient is given plenty of fluids, and sometimes diuretics are administered to accelerate drug elimination.

• Electrolyte balance control – in cases of severe vomiting and diarrhea, intravenous fluid therapy may be necessary to prevent dehydration.

• Hemodialysis – used in severe cases when the kidneys are unable to excrete the drug, preventing toxic accumulation.

If overdose is suspected, seek medical help immediately, as severe complications may develop hours after excessive drug intake.

Purbac is a combined antibacterial drug with bactericidal activity. It kills bacteria by blocking their ability to reproduce.

Its pharmacological action is based on a combination of two active ingredients that act on different stages of folic acid synthesis in bacterial cells:

• Sulfamethoxazole inhibits the synthesis of dihydrofolic acid, which is essential for bacterial growth and reproduction.

• Trimethoprim inhibits the enzyme dihydrofolate reductase, preventing the conversion of dihydrofolic acid into its active form.

As a result, Purbac disrupts two consecutive stages in the biosynthesis of purines and nucleic acids—critical components for bacterial survival.

The drug is active against both Gram-positive and Gram-negative bacteria, including:

• Streptococcus pneumoniae

• Escherichia coli

• Klebsiella spp.

• Haemophilus influenzae

• Staphylococcus aureus

• Proteus mirabilis

• Enterobacter spp.

• Shigella spp.

• Salmonella spp.

This makes Purbac suitable for treating infections in the respiratory tract, urinary system, gastrointestinal tract, and skin.

The pharmacokinetics of Purbac determine its efficacy and dosing regimen:

• Bioavailability – approximately 90%. When taken orally, the drug is rapidly and almost completely absorbed from the gastrointestinal tract.

• Maximum blood concentration is reached within 1–4 hours after administration.

• Plasma protein binding – around 66% for sulfamethoxazole and 45% for trimethoprim.

• Half-life – 10–12 hours, allowing for twice-daily dosing.

• Metabolism – occurs in the liver, where both components undergo partial transformation.

• Excretion – primarily via the kidneys:

• 30–50% of sulfamethoxazole is excreted unchanged.

• 50–60% of trimethoprim is also excreted unchanged.

Due to high urinary concentrations, Purbac is especially effective for urinary tract infections. However, in patients with renal impairment, dose adjustment is necessary to avoid drug accumulation.

• Antibacterial agents, combination of sulfonamides and trimethoprim.

Septrin should not be used in pregnancy, particularly in the first trimester, unless clearly necessary. Folate supplementation should be considered if Septrin is used in pregnancy.

Sulfamethoxazole competes with bilirubin for binding to plasma albumin. As significantly maternally derived drug levels persist for several days in the newborn, there may be a risk of precipitating or exacerbating neonatal hyperbilirubinaemia, with an associated theoretical risk of kernicterus, when Septrin is administered to the mother near the time of delivery. This theoretical risk is particularly relevant in infants at increased risk of hyperbilirubinaemia, such as those who are preterm and those with glucose-6-phosphate dehydrogenase deficiency.

Lactation

The components of Septrin (trimethoprim and sulfamethoxazole) are excreted in breast milk. Administration of Septrin should be avoided in late pregnancy and in lactating mothers where the mother or infant has, or is at particular risk of developing, hyperbilirubinaemia. Additionally, administration of Septrin should be avoided in infants younger than eight weeks in view of the predisposition of young infants to hyperbilirubinaemia.

There have been no studies to investigate the effect of Septrin on driving performance or the ability to operate machinery. Further a detrimental effect on such activities cannot be predicted from the pharmacology of the drug. Nevertheless the clinical status of the patient and the adverse events profile of Septrin should be borne in mind when considering the patients ability to operate machinery.

As co-trimoxazole contains trimethoprim and a sulphonamide the type and frequency of adverse reactions associated with such compounds are expected to be consistent with extensive historical experience.

Data from large published clinical trials were used to determine the frequency of very common to rare adverse events. Very rare adverse events were primarily determined from post-marketing experience data and therefore refer to reporting rate rather than a "true" frequency. In addition, adverse events may vary in their incidence depending on the indication.

The following convention has been used for the classification of adverse events in terms of frequency:- Very common >1/10, common >1/100 and <1/10, uncommon >1/1000 and <1/100, rare >1/10,000 and <1/1000, very rare <1/10,000.

At the high dosages used for PCP management severe hypersensitivity reactions have been reported, necessitating cessation of therapy. If signs of bone marrow depression occur, the patient should be given calcium folinate supplementation (5-10 mg/day). Severe hypersensitivity reactions have been reported in PCP patients on re-exposure to co-trimoxazole, sometimes after a dosage interval of a few days. Rhabdomyolysis has been reported in HIV positive patients receiving co-trimoxazole for prophylaxis or treatment of PCP.

Nausea, vomiting, dizziness and confusion are likely signs/symptoms of overdosage. Bone marrow depression has been reported in acute trimethoprim overdosage.

If vomiting has not occurred, induction of vomiting may be desirable. Gastric lavage may be useful, though absorption from the gastrointestinal tract is normally very rapid and complete within approximately two hours. This may not be the case in gross overdosage. Dependant on the status of renal function administration of fluids is recommended if urine output is low.

Both trimethoprim and active sulfamethoxazole are moderately dialysable by haemodialysis. Peritoneal dialysis is not effective.

Pharmacotherapeutic group: Combinations of sulfonamides and trimethoprim, incl. derivatives; ATC code: J01EE01

Mode of Action

Septrin is an antibacterial drug composed of two active principles, sulfamethoxazole and trimethoprim. Sulfamethoxazole is a competitive inhibitor of dihydropteroate synthetase enzyme. Sulfamethoxazole competitively inhibits the utilisation of para-aminobenzoic acid (PABA) in the synthesis of dihydrofolate by the bacterial cell resulting in bacteriostasis. Trimethoprim binds to and reversibly inhibits bacterial dihydrofolate reductase (DHFR) and blocks the production of tetrahydrofolate. Depending on the conditions the effect may be bactericidal. Thus trimethoprim and sulfamethoxazole block two consecutive steps in the biosynthesis of purines and therefore nucleic acids essential to many bacteria. This action produces marked potentiation of activity in vitro between the two agents.

Mechanism of resistance

In vitro studies have shown that bacterial resistance can develop more slowly with both sulfamethoxazole and trimethoprim in combination that with either sulfamethoxazole or trimethoprim alone.

Resistance to sulfamethoxazole may occur by different mechanisms. Bacterial mutations cause an increase the concentration of PABA and thereby out-compete with sulfamethoxazole resulting in a reduction of the inhibitory effect on dihydropteroate synthetase enzyme. Another resistance mechanism is plasmid-mediated and results from production of an altered dihydropteroate synthetase enzyme, with reduced affinity for sulfamethoxazole compared to the wild-type enzyme.

Resistance to trimethoprim occurs through a plasmid-mediated mutation which results in production of an altered dihydrofolate reductase enzyme having a reduced affinity for trimethoprim compared to the wild-type enzyme.

Trimethoprim binds to plasmodial DHFR but less tightly than to bacterial enzyme. Its affinity for mammalian DHFR is some 50,000 times less than for the corresponding bacterial enzyme.

Many common pathogenic bacteria are susceptible in vitro to trimethoprim and sulfamethoxazole at concentrations well below those reached in blood, tissue fluids and urine after the administration of recommended doses. In common with other antibiotics, however, in vitro activity does not necessarily imply that clinical efficacy has been demonstrated and it must be noted that satisfactory susceptibility testing is achieved only with recommended media free from inhibitory substances, especially thymidine and thymine.

Breakpoints

EUCAST

Enterobacteriaceae: S≤ 2 R> 4

S. maltophilia: S≤ 4 R> 4

Acinetobacter: S≤ 2 R> 4

Staphylococcus: S≤ 2 R> 4

Enterococcus: S≤ 0.032 R> 1

Streptococcus ABCG: S≤ 1 R> 2

Streptococcus pneumoniae: S≤ 1 R> 2

Hemophilus influenza: S≤ 0.5 R> 1

Moraxella catarrhalis: S≤0.5 R >1

Psuedomonas aeruginosa and other non-enterobacteriaceae: S≤ 2* R> 4*

S = susceptible, R = resistant. *These are CLSI breakpoints since no EUCAST breakpoints are currently available for these organisms.

Trimethoprim: sulfamethoxazole in the ratio 1:19. Breakpoints are expressed as trimethoprim concentration.

Antibacterial Spectrum

The prevalence of resistance may vary geographically and with time for selected species and local information on resistance is desirable, particularly when treating severe infections. As necessary, expert advice should be sought when the local prevalence of resistance is such that the utility of the agent in at least some types of infections is questionable. This information gives only an approximate guidance on probabilities whether microorganisms will be susceptible to trimethoprim/sulfamethoxazole or not.

Trimethoprim/sulfamethoxazole susceptibility against a number of bacteria are shown in the table below:

After oral administration trimethoprim and sulfamethoxazole are rapidly and nearly completely absorbed. The presence of food does not appear to delay absorption. Peak levels in the blood occur between one and four hours after ingestion and the level attained is dose related. Effective levels persist in the blood for up to 24 hours after a therapeutic dose. Steady state levels in adults are reached after dosing for 2-3 days. Neither component has an appreciable effect on the concentrations achieved in the blood by the other.

Trimethoprim is a weak base with a pKa of 7.4. It is lipophilic. Tissue levels of trimethoprim are generally higher than corresponding plasma levels, the lungs and kidneys showing especially high concentrations. Trimethoprim concentrations exceed those in plasma in the case of bile, prostatic fluid and tissue, saliva, sputum and vaginal secretions. Levels in the aqueous humor, breast milk, cerebrospinal fluid, middle ear fluid, synovial fluid and tissue (intestinal) fluid are adequate for antibacterial activity. Trimethoprim passes into amniotic fluid and foetal tissues reaching concentrations approximating those of maternal serum.

Approximately 50% of trimethoprim in the plasma is protein bound. The half-life in man is in the range 8.6 to 17 hours in the presence of normal renal function. It is increased by a factor of 1.5 to 3.0 when the creatinine clearance is less than 10 ml/minute. There appears to be no significant difference in the elderly compared with young patients.

The principal route of excretion of trimethoprim is renal and approximately 50% of the dose is excreted in the urine within 24 hours as unchanged drug. Several metabolites have been identified in the urine. Urinary concentrations of trimethoprim vary widely.

Sulfamethoxazole is a weak acid with a pKa of 6.0. The concentration of active sulfamethoxazole in a variety of body fluids is of the order of 20 to 50% of the plasma concentration.

Approximately 66% of sulfamethoxazole in the plasma is protein bound and the principal route of excretion of sulfamethoxazole is renal. The half-life in man is approximately 9 to 11 hours in the presence of normal renal function. There is no change in the half-life of active sulfamethoxazole with a reduction in renal function but there is prolongation of the half-life of the major, acetylated metabolite when the creatinine clearance is below 25 ml/minute.

The principle route of excretion of sulphamethoxazole is renal; between 15% and 30% of the dose recovered in the urine is in the active form. In elderly patients there is a reduced renal clearance of sulfamethoxazole.

Reproductive toxicology:

At doses in excess of recommended human therapeutic dose, trimethoprim and sulfamethoxazole have been reported to cause cleft palate and other foetal abnormalities in rats, findings typical of a folate antagonist. Effects with trimethoprim were preventable by administration of dietary folate. In rabbits, foetal loss was seen at doses of trimethoprim in excess of human therapeutic doses.

In addition to active ingredients, Purbac contains excipients that ensure stability, controlled release, and ease of use.

Key Components:

• Starch – serves as a filler, giving the tablet its required shape and structure.

• Magnesium stearate – functions as a lubricant, preventing the ingredients from clumping together and facilitating tablet manufacturing.

• Sodium starch glycolate – promotes rapid tablet disintegration in the stomach, ensuring even and complete release of active ingredients.

• Propylene glycol – acts as a solvent and stabilizer, improving the solubility of some components.

• Nipasol – a preservative that prevents drug degradation during storage.

The composition of excipients may slightly vary depending on the dosage form (tablets, suspension, injection solution).

Before use, check the composition, especially if the patient has allergies to excipients.

Purbac remains effective for 3 years from the date of manufacture. However, the shelf life may vary depending on the dosage form.

Always check the expiration date on the packaging before use. Expired medication should not be used, as it may lose therapeutic efficacy or become unsafe.

To maintain stability and effectiveness, Purbac must be stored properly:

• Tablets – store at a temperature below 25°C, in a dry place away from direct sunlight and moisture.

• Oral suspension – store in the refrigerator at 2–8°C. Do not freeze as this may alter its properties. Shake the bottle well before each use to evenly distribute active ingredients.

• Injection solution – store at room temperature, in a dark place, away from heat sources and direct light.

Always keep the medication out of reach of children to prevent accidental ingestion.

Purbac is available in different forms, each with its specific packaging. This is important for storage, accurate dosing, and safe administration.

• Tablets – packaged in blisters of 10 tablets, enclosed in a carton box. The number of blisters in a package depends on the dosage and treatment course. Tablets have a protective coating for easier swallowing.

• Oral suspension – supplied in a 100 ml bottle. A measuring spoon or dosing syringe may be included for accurate dosing. Shake the bottle before use.

• Injection solution – comes in 5 ml ampoules, used only in hospitals under medical supervision.

Before use, always inspect the packaging. If a blister is damaged, the suspension has changed color, or an ampoule contains sediment, do not use the medication. Instead, consult a pharmacist or doctor for a replacement.

Some patients require additional precautions when using Purbac. This is especially relevant for elderly individuals and those undergoing long-term therapy.

• Elderly patients are often advised to take folic acid supplements, as Purbac can reduce folate levels in the body. Folate deficiency may lead to anemia, fatigue, dizziness, and other complications. This is particularly important during prolonged antibiotic therapy.
  
  

• Do not use expired medication. Over time, active ingredients may degrade, making the drug not only ineffective but potentially unsafe.
  
  

How to dispose of the drug properly?

Antibiotics should not be thrown into household waste or flushed down the drain — this contributes to the spread of antibiotic-resistant bacteria in the environment.
The best approach is to inquire at a pharmacy or healthcare facility about where to safely return expired medications.

If the packaging is damaged or the medicine is no longer needed, dispose of it according to local sanitary regulations, not in a regular trash bin.

Purbac is officially registered and distributed in South Africa.

• Aspen Pharmacare (South Africa)

• The medication is available by prescription only.

Taking Purbac requires adherence to specific rules to ensure maximum safety and effectiveness of treatment. It’s important to follow your doctor's recommendations and avoid common mistakes that can reduce the drug’s efficacy or increase the risk of side effects.

• Use only as prescribed. Purbac is an antibiotic that requires precise dosing and course duration. Do not change the regimen on your own — this may reduce its effectiveness and contribute to bacterial resistance.
  
  

• Do not stop treatment prematurely. Even if symptoms disappear, it is important to complete the full course. Stopping too early can leave some bacteria alive, making the infection return in a more resistant form.
  
  

• Avoid prolonged sun exposure. Purbac increases skin sensitivity to UV radiation (photosensitization), which raises the risk of sunburn and irritation. If you must be outside, wear long-sleeved clothing and use sunscreen.
  
  

• Report side effects to your doctor. If you experience rash, itching, nausea, dizziness, or other unusual symptoms during treatment, consult your physician to adjust the therapy.
  
  

Following these recommendations will help minimize side effects and maximize treatment effectiveness. When used correctly, Purbac is a safe and effective option for treating bacterial infections.

• J01EE01 (Sulfamethoxazole in combination with trimethoprim).

A00.9 Cholera, unspecified

A01.0 Typhoid fever

A01.4 Paratyphoid fever, unspecified

A02 Other Salmonella infections

A09 Diarrhea and gastroenteritis of presumed infectious origin (dysentery, bacterial diarrhea)

A23.9 Brucellosis, unspecified

A39 Meningococcal infection

A42 Actinomycosis

A54 Gonococcal infection

A55 Chlamydial lymphogranuloma (venereal)

A56 Other sexually transmitted chlamydial diseases

A57 Chancroid

A74 Other diseases caused by chlamydia

A75 Typhus

B49 Mycosis, unspecified

B58 Toxoplasmosis

B59 Pneumocystis cystis

G00 Bacterial meningitis, not elsewhere classified categories

G04 Encephalitis, myelitis and encephalomyelitis

H60 Otitis externa

H66 Suppurative and unspecified otitis media

H70 Mastoiditis and related conditions

J02.9 Acute pharyngitis, unspecified

J03.9 Acute tonsillitis, unspecified (agranulocytic angina)

J06 Acute upper respiratory tract infection of multiple and unspecified sites

J11 Influenza, virus unidentified

J18 Pneumonia, unspecified

J22 Acute lower respiratory tract infection, unspecified

J32 Chronic sinusitis

J40 Bronchitis, not specified as acute or chronic

J42 Chronic bronchitis, unspecified

J47 Bronchiectatic disease [bronchiectasis]

J85 Lung abscess and mediastinum

J86 Pyothorax

K29.5 Chronic gastritis, unspecified

K52 Other noninfectious gastroenteritis and colitis

K81 Cholecystitis

K83.0 Cholangitis

L02 Skin abscess, furuncle and carbuncle

L03 Cellulitis

L08.0 Pyoderma

L08.9 Local infection of skin and subcutaneous tissue, unspecified

M60.0 Infectious myositis

M65 Synovitis and tenosynovitis

M65.0 Tendon sheath abscess

M71.0 Bursal abscess

M71.1 Other infectious bursitis

M86 Osteomyelitis

N12 Tubulointerstitial nephritis, not specified as acute or chronic

N15 Other tubulointerstitial diseases of kidney

N30 Cystitis

N34 Urethritis and urethral syndrome

N39.0 Urinary tract infection of unspecified site

N41.9 Inflammatory disease of prostate, unspecified

N49 Inflammatory diseases of male genital organs, not elsewhere classified

N70 Salpingitis and oophoritis

N73.9 Inflammatory diseases of female pelvic organs, unspecified

N74.3 Gonococcal inflammatory diseases of female pelvic organs (A54.2+)

N74.4 Inflammatory diseases of female pelvic organs due to chlamydia (A56.1+)

R09.1 Pleurisy

T79.3 Posttraumatic wound infection, not elsewhere classified

Z100* CHAPTER XXII Surgical practice