Primpex Cotrimoxazole Oral Suspension Caplets and Tablets


Co-trimoxazole Oral Presentations





The active ingredients in Primpex are:
Trimethoprim (2,4 – diamino-5-(3,4,5-trimethoxybenzyl-Pyrimidine).
Sulphomethoxazole (5-methyl-3 sulfanilamido-isoxozole).



Primpex Tablets: Each white, round, biconvex uncoated tablet is scored and embossed SKG D3A on one side and plain on the other side and contains 80mg Trimethoprim B.P and 400mg sulphamethoxazole B.P.

Primpex DS caplets: Each white, uncoated caplet is embossed G3A SKG on one side and scored on the other side and contains 160mg Trimethoprim B.P. and 800mg sulphamenthoxazole B.P.

Suspensions: Each 5ml of flavoured suspension contains 40mg Trimethoprim B.P. and 200mg sulphamethoxazole B.P.



Primpex’s antibacterial effect covers a wide range of gram-positive and gram-negative organisms such as staphylococci, pneumococci, Haemophilius, streptococci, neisseria, E.coli, proteus mirabilis, proteus vulgaris, Bordetella, Salmonella, Klebsiela-Aerobacter, Shigella, Vibrio cholerae, Brucella, Pseudomonas, Pneumocystis Carinii, Serratia, Marcescen, Yersinia and Nocardia.



Primpex is indicated for the treatment of sensitive bacterial infections of the:

Respiratory Tract: Acute and chronic bronchitis, Pneumonia, Pneumocystis carinii pneumonitis, bronchiectasis, otitis media, sinusitis, Pharyngitis.

Urinary Tract: Acute and chronic cystitis, Pyelonephritis, Urethritis, Prostotitis. Acute upper and lower urinary tract infections. Long-term prophylaxis of recurrent or suppression of chronic infections following sterilisation of the urine.

Genital Tract: Oro-pharyngeal and ano-rectal gonorrhoea infection, gonococcol urethritis, salpingitis, chancroid, lymphogronuloma venereum and granuloma inguinale venereum.

Gastrointestinal Tract: Thyphoid and Parathyphoid fever, thyphoid carrier, State and bacillary dysentery, cholera, (as an adjunct to fluid and electrolyte replacement). Shigellosis, gastroenteritis due to entero-pathogens and biliary tract infections.

Skin and Soft Tissues: Pyodema furuncles, abscesses and infected wounds.

Other Bacterial infections: Acute and chronic osteomyelitis, acute brucellosis, septicaemia due to sensitive organisms, Nocardiosis, mycetoma, (except when caused by the true fungi).

Protozoal Infections: Malarial due to P. Falciparum, prophylaxis of infections in immune-compromised patients.



The two components of primpex interfere with the bacterial synthesis of tetrahydrofolic acid, an essential stage in the production of thymidine, Purines and subsequently nucleic acids.



Primpex should be taken with some food or drink to minimise the possibility of gastro-intestinal disturbances.



PRIMPEX TABLET Morning Evening
Adults and Children over 12 years (2 tablets every 12 hours) 1 2
Children 6-12 years (1 tablet every 12 hours) 1 1
Adults and children over 12 years (1 tablet every 12 hours) 1 1
Children 6-12 years (½ tablet every 12 hours) ½ ½
Children 6-12 years 10ml (two teaspoonfuls) every twelve hours 1 2
Children 6 months – 5 years
5ml (one teaspoonful) every 12 hours
1 1
Children 6 weeks – 5 months
2.5ml (half spoonful) every 12 hours
½ ½

Children below 6 weeks not recommended.

The above Dosage regimen corresponds approximately to an average dose of 6mg Trimethoprim and 30mg sulphamethoxazole per kilogram body weight per 24hrs. For severe infections the dosage shown may be increased by 50%.

Treatment should be continued until the patient has been symptom free for two days, majority will require treatment for at least 5 days.



Unless otherwise specified standard dosage applies.

Chronic Prostatitis

It may be advisable to use a higher than standard dosage initially. The course of treatment should last for three months to reduce the risk of relapse.

Pneumocystis carinii pneumonitis

Treatment 20mg trimethroprim and 100mg sulphamethoxazole per kilogram body weight per day in two or more divided doses for two weeks.

Prevention: Standard dosage for the duration of the period at risk.


Dosage restricted to Adults only.

Uncomplicated cases: 4 tablets every 12 hours for two days or 5 tablets followed by a further dose of 5 tablets eight hours later.

If poor patient compliance is expected a single dose of 8 tablets taken under supervision may be employed.

Oro-pharyngeal gonococcal infections: 2 tablets three times daily for Seven days or 9 tablets daily for five days.

Chancroid: Standard dosage should be continued for 10-15 days.
Granuloma inguinale: Standard dosage should be continued for up to 2weeks.

Acute Brucellosis: A higher than standard dosage should be used initially and treatment continued for a period of at least four weeks and may be repeated.

Malaria due to P. Falciparum: Four tablets twice daily for two days may be given as an alternative regimen for adults. Children would require a reduced dose.

Typhoid and paratyphoid carriage: Standard dosage treatment should be continued for at least 1-3 months.

Long-term prophylaxis of recurrent or suppression of chronic infection following sterilisation of the urine: Adults and children over 12years – 1 tablet every night. Children aged 12years and under – A single nightly dose of 2mg Trimethoprim and 10mg sulpamethoxazole per kg body weight.

Treatment may be continued for 3- 12 months or more as appropriate.



At the recommended dosage Primpex is usually well tolerated. Of the reported adverse effects most are mild and comprise nausea (with or without vomiting) and drug rashes. As with a great variety of other drugs, Primpex has in isolated cases been associated with the Stevens-Johnson and Lyell’s syndromes.

Heamatological changes have been reported, the majority being mild, Asymptomatic and reversible on withdrawal of the drug. The changes mainly took the form of leukopenia, neutropenia and thrombocytapenia. Very rarely, agranulocytosis, Megaloblastic anaemia and purpura occurred.



In patient with impaired renal function, the dosage of primpex should be reduced or the interval between doses prolonged in order to prevent accumulation in the blood.

Determination of plasma drug concentrations is recommended in such patients. Especially in the elderly, there is a possibility of haematological changes indicatives of folic acid deficiency; these are reversible by folinic acid and therapy. Regular blood counts are advisable when primpex is given for prolonged periods. An adequate urinary – should be maintained at all times during therapy and treatment should be discontinued immediately if a skin rash appears or blood disorder develop.

An adequate fluid intake should be maintained to reduce the risk of crystalluria.



Primpex should not be administered to patients with a history of hypersensitivity to sulponamides orTrimethoprim. It is contraindicated in patients with marked liver Parenchymal damage, severe renal insufficiency when repeated determinations of the Plasma concentration cannot be made. Except in rare cases Primpex should not be given to patients with serious haematological disorder. The combination has occasionally been administered to patients receiving cytotoxic agents for the treatment of leukemias, without evidence of any adverse effect of the bone marrow or peripheral blood. It is contraindicated in patients with megaloblastic anaemia due to folate deficiency.

For safety reasons, Primpex is contraindicated during pregnancy. If pregnancy cannot be excluded, possible risks should be balanced against the expected therapeutic effect.

Primpex should not be given to premature and new born infants during the first few weeks of life.


The safety of Primpex in human pregnancy has not been established. Despite the excretion at Trimethoprim and sulphamethoxazole into breast milk the administration of primpex to lactating women represents a negligible risk to the sucking infant.



Co-trimoxazole prolongs the half -life of phenytoin. Concurrent use of rifampicin and co-trimoxazole results in shortening of the plasma half life of Trimethoprim after a period of about one week. Reversible deterioration in renal function has been observed in patent treated with co-trimoxazole and cyclosporin following renal transplantation.
Co-trimoxazole has been shown to potentiate the anticoagulant activity of warfarin via stereo-selective inhibition of its metabolism. In elderly patients concurrently receiving diurectics, mainly thiazides, there appears to be an increased risk of thrombocytopenia with or without purpura.

Occasional reports suggest that patients receiving pyrimethamine as Malaria prophylaxis in doses exceeding 25mg weekly may develop megaloblastic anaemia if Primpex is prescribed concurrently.



Storage Recommendations

Adult Tablets: Store below 35°C and protect from light.

Pediatric Suspension: Store below 25°C and protect from light.

May be diluted with syrup B.P.

Shake well before use.


Further information available on request:

SKG Pharma Limited

7/9, Sapara Street,

Ikeja, Lagos.


Manufactured in Nigeria by

SKG-Pharma Limited

7/9, Sapara Street,

Ikeja, Lagos.

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