(Co-trimoxazole)- SULPHAMETHOXAZOLE + TRIMETHOPRIM.
Coptrine® (Co-trimoxazole) Tablet contains: Sulphamethoxazole 400mg and Trimethoprim 80mg while 5ml Coptrine® Suspension contains Sulphamethoxazole 200mg and Trimethoprim 40mg
PHARMACOLOGY
Coptrine® (Co-trimoxazole) is a chemotherapeutic agent exhibiting bactericidal activity against a wide range of gram–negative and gram–positive organisms such as Streptococci, Staphylococci, Pneumococci, E. coli, Bordetella, Haemophilus influenzae, Neisseria, Salmonella , Klebsiella Aerobacter, Pneumocyctis carinii, Brucella, Pseudomonas, Proteus mirabilis. The combination of Sulphamethoxazole and Trimethoprim (5:1) in Coptrine® may prevent emergence of bacterial resistance better than when either agent is used alone. Their synergistic effect is attributed to the inhibition of tetrahydrofolic acid production – a cofactor for the synthesis of purines thymidine and DNA, at two sequential steps in the folic acid biosynthesis.
Sulphamethoxazole and Trimethoprim, both undergo hepatic metabolism and renal excretion. Sulphamethoxazole inhibits the incorporation of para amino benzoic acid (PABA) into folic acid whereas Trimethoprim blocks the reduction of dihydrofolic acid to tetrahydrofolic acid.
INDICATIONS
Urinary tract infections (UTI); Ear, Nose and Throat infections (ENT); Acute otitis media in children; lower respiratory tract infection(acute exacerbation of chronic bronchitis in adults); traveller’s diarrhea in adult; shigellosis and enteritis; Pneumocystis carinii pneumonia.
CONTRAINDICATIONS
Hypersensitivity to Trimethoprim or Sulphonamides, hepatic or renal failure, megalobastic anaemia due to folate deficiency; pregnancy, breast feeding, premature infants and infants less than two months old.
INTERACTIONS
- Warfarin – Co-trimoxazole potentiates the anticoagulant effect
- Phenyton – Inhibits the hepatic metabolism of phenytoin thereby
increasing its anti folate effect and plasma concentration.
- Sulphonylureas – Enhanced antidiabetic effect.
- Pyrimethamine and products containing pyrimethamine – increased risk of antifolate effect.
- A decrease in the therapeutic effect of Cyclosporin and an increased risk of nephrotoxicity may occur during co-administration with trimethoprim.
PRECAUTIONS
Impaired renal or hepatic function, folate deficiency (such as in the elderly, chronic alcoholics)
Patients on anticonvulsant treatment, patients with malabsorption syndrome, malnourished patients, severe allergy or bronchial asthma.
A dose-related haemolysis may occur in G6PD deficient cases. Discontinue at the first appearance of skin rash or any sign of adverse reaction.
Periodic complete blood counts during prolonged therapy plus folate supplement.
Maintain adequate fluid intake to prevent crystalluria and stone formation
KEEP OUT OF THE REACH OF CHILDREN
ADVERSE EFFECTS
Nausea, vomiting, anorexia, glossitis, stomatitis, allergic reactions like rash, urticaria, rarely agranulocytosis, aplastic or haemolytic or megaloblastic anaemia and thrombocytopenia; Stevens-Johnson syndrone, erythema multiforme, toxic epidermal necrolysis, photosensitization, mild and transient jaundice; headache, depression, hallucinations; arthralgia, myalgia, pulmonary infiltration, shortness of breath, weakness, fatigue, insomnia. Permanent impairment of renal function may occur in patients with renal disease.
STANDARD DOSAGE AND ADMINISTRATION
| Morning* | Evening* | |
| Coptrine® Tablet Adult and Children over 12years Children 6 years to 12 years | 2 tablets 1 tablet | 2 tablets 1 tablet |
| Coptrine®suspension Children 6 weeks to 5 months Children 6 months to 5 years Children 6 years to 5 years | 2.5ml 5ml 10ml | 2.5 5ml 10ml |
* (Morning and evening indicate 12 hourly)
Dosages may be increased by 50% in severe infections.
In Pneumocystis carinii Pneumonia
Treatment: 20mg trimethoprim and 100mg sulphamethoxazole per kg body weight daily in divided doses for 2 weeks.
Prevention: standard dosage for the duration of the risk period
In Lymphogranuloma venereum, Granuloma inguinale, chancroid.
Standard dosage for up to 2 weeks.
In Gonorrhea
Adult – standard dosage for up to 7 days or 1920mg 12 hourly for 2 days.
In Oro–pharynmeal gonococcal infection.
960mg 3 times daily for 7 days or 1440mg 3 times daily for 3 days.
In Acute brucellosis.
Initial dose should be higher than standard dose; treatment should continue for at least 1 month thereafter repeated courses could be beneficial.
Presentation
Coptrine® (Co-trimoxazole) is available as x 1000 tablets, in blister pack of 10 x 10 tablets and as 50ml paediatric suspension.
STORAGE CONDITIONS
Store below 300c. Protect from light and moisture.