SEPTRIN Concentrate for solution for infusion Ref.[108387] Active ingredients: Sulfamethoxazole Trimethoprim

Posology

Standard dosage recommendations for acute infections

Adults (>18 years old):

The standard dosage for children is equivalent to approximately 6 mg trimethoprim and 30 mg sulfamethoxazole per kg body weight per day, given in two equally divided doses. The schedules for children are according to the child’s age and provided in the tables below:

Children over 12 years old (>12 to <18 years old):

Children aged 12 years and under (>6 weeks to <12 years old):

For severe infections in all age groups, dosage may be increased by 50% for severe infections.

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

Elderly patients

See section 4.4

Impaired renal function

Dosage recommendation

Adults (>18 years old) and Children over 12 years old (>12 to <18 years old):

No information is available for children aged 12 years and under with renal failure. See section 5.2 for the pharmacokinetics in the paediatric population with normal renal function of both components of Septrin.

Impaired hepatic function

Caution should be exercised when treating patients with severe hepatic impairment as there may be changes in the absorption and biotransformation of trimethoprim and sulfamethoxazole.

Measurements of plasma concentrations of sulfamethoxazole at intervals of two to three days are recommended in samples obtained 12 hours after administration of Septrin. If the concentration of total sulfamethoxazole exceeds 150 mcg/ml then treatment should be interrupted until the value falls below 120 mcg/ml.

Pneumocystis jirovecii pneumonitis (PJP)

Treatment – children aged 12 years and under (>6 weeks to <12 years old); children over 12 years old (>12 to <18 years old) and adults (>18 years old)

20 mg trimethoprim and 100 mg sulfamethoxazole per kg of body weight per day in two or more divided doses. The course is two weeks, but oral therapy should be substituted as soon as it is appropriate. The steady state or serum level of trimethoprim should be maintained at 5 mcg/ml or higher for maximum efficacy. The aim is to obtain peak plasma or serum levels of trimethoprim of greater than or equal to 5 microgram/ml (verified in patients receiving 1-hour infusions of intravenous Septrin). (See section 4.8)

Prevention

Standard dosage as described under acute infections for the duration of the period at risk.

Nocardiosis

There is no consensus on the most appropriate dosage. Adult doses of 480 mg trimethoprim/2400 mg sulfamethoxazole to 640 mg trimethoprim/3200 mg sulfamethoxazole daily for up to three months have been used.

Brucellosis

It may be advisable to use a higher than standard dosage initially when the intravenous route may be preferred. Treatment should continue for a period of at least four weeks and repeated courses may be beneficial. Septrin should be given in combination with other agents in line with national treatment guidelines.

Toxoplasmosis

There is no consensus on the most appropriate dosage for the treatment or prophylaxis of this condition. The decision should be based on clinical experience. Doses of 480 mg or 960 mg of trimethoprim-sulfamethoxazole twice daily for three months have been used for prophylaxis and 40 mg/kg/day or 120 mg/kg/day for a mean of 25 days for the treatment of toxoplasmosis in patients with HIV.

Method of administration

Septrin for Infusion is for administration only by the intravenous route and must be diluted before administration.

It is intended that Septrin for Infusion should be used only during such a period as the patient is unable to accept oral therapy, where initiation of treatment is particularly urgent or for convenience if the patient is already receiving intravenous fluids. Although Septrin for Infusion is useful in critically ill patients, there may be no therapeutic advantage over the oral preparation.

For instructions on dilution of the product before administration, see section 6.6.

Symptoms

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

The maximum tolerated dose in humans is unknown.

Management

Dependent 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.

In cases of known, suspected or accidental overdose, stop therapy.

Acidification of the urine will increase the elimination of trimethoprim. Inducing diuresis plus alkalinisation of urine will enhance the elimination of sulfamethoxazole. Alkalinisation will reduce the rate of elimination of trimethoprim. Calcium folinate (5 to 10 mg/day) will reverse any folate deficiency effect of trimethoprim on the bone marrow should this occur. General supportive measures are recommended.

3 years.

Do not store above 30°C.

Keep the ampoule in the outer carton to protect from light.

5ml Type 1, clear-neutral glass ampoule.

Pack size: Box of 10x5ml ampoules.

Septrin for Infusion must be diluted before administration.

DILUTION SHOULD BE CARRIED OUT IMMEDIATELY BEFORE USE. After adding Septrin for Infusion to the infusion solution shake thoroughly to ensure complete mixing.

If visible turbidity or crystallisation appears at any time before or during an infusion, the mixture should be discarded.

It is recommended that Septrin for Infusion is diluted according to the following schedules:

One ampoule (5 ml) added to 125 ml infusion solution.

Two ampoules (10 ml) added to 250 ml infusion solution.

Three ampoules (15 ml) added to 500 ml infusion solution.

Septrin for Infusion is known to be compatible, when diluted as recommended above, with the following fluids:

Glucose Intravenous Infusion BP (5% w/v and 10% w/v);
Sodium Chloride Intravenous Infusion BP (0.9% w/v);
Sodium Chloride (0.18% w/v) and Glucose (4% w/v) Intravenous Infusion BP;
Dextran 70 Intravenous Infusion BP (6% w/v) in glucose (5% w/v) or normal saline;
Dextran 40 Intravenous Infusion BP (10% w/v) in glucose (5% w/v) or normal saline;
Ringer’s Solution for Injection BPC 1959.

The duration of the infusion should be approximately one to one and a half hours, but this should be balanced against the fluid requirements of the patient.

If higher concentrations are required, one ampoule (5 ml) may be diluted with 75 ml of glucose 5% w/v in water. The resultant solution, whilst being clear to the naked eye, may on occasion exceed the BP limits set for particulate matter in large volume parenterals. The solution should be infused over a period not exceeding one hour.

Discard any unused solution.