Pharmacy Guide
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Pharmacy Guide
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Tolbutamide Tablets BP 500 mg
⚠ This medicine appears to have been discontinued
The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.
If you were prescribed this medicine, other products containing Tolbutamide may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.
What it is and what it is used for
for The name of your medicine is Tolbutamide Tablets BP 500 mg (referred to as Tolbutamide Tablets in this leaflet). Tolbutamide Tablets contain the active ingredient tolbutamide, which belongs to a group of medicines called oral hypoglycaemics. Tolbutamide Tablets are used to treat mild to moderate diabetes of the non-insulin dependent type (type 2 or maturity onset diabetes), which does not respond to dietary measures. This usually only occurs in adults. Tolbutamide Tablets lower the sugar content in your blood if this is too high. If you are overweight, treatment with Tolbutamide Tablets should not replace your dietary restrictions.
What you need to know before you take it
e Tolbutamide Tablets Do not take Tolbutamide Tablets
- if you are allergic to Tolbutamide Tablets or any of the other ingredients of this medicine (listed in section 6).
- if you have diabetes that needs to be treated by insulin (type 1 or insulin dependent diabetes)
- if you have ever had diabetic ketoacidosis (the symptoms of this include unusual smelling breath, drowsiness, confusion, feeling or being sick and difficulty breathing)
- if you have serious liver or kidney problems
- if you have serious problems with your adrenal or thyroid glands
- if you are under unusual stress
- if you need an operation
- if you are in the first trimester of pregnancy
- if you have an uncommon inherited blood disorder called porphyria
- if you are breast-feeding. Warning and precautions Talk to your doctor or pharmacist before taking Tolbutamide Tablets
- if you experience the symptoms of low blood sugar (such as sweating, pallor, hunger, faster heart beat and feeling unwell)
- if you are debilitated ('run down') or are elderly
- if you have had any problems taking medicines used to treat diabetes
- if you have an infection, or the number of sore throats or fevers you experience increases or you develop spontaneous bruising or bleeding as your doctor may wish to test your blood
- if you have mild kidney disease
- if you have an inherited condition where your red blood cells do not produce enough of the enzyme G6PD (glucose 6 phosphate dehydrogenase). Children and adolescents Tolbutamide Tablets are not for use in children and adolescents. Other medicines and Tolbutamide Tablets Tell your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines, including any medicines obtained without a prescription and herbal remedies. This is especially important if you are taking any of the following:
- medicines which provide contraception e.g. oral contraceptives (the pill)
- medicines known as beta-blockers (e.g. propranolol, atenolol) and thiazide diuretics (e. g. Bendroflumethiazide, hydrochlorothiazide) which are used to treat a range of heart problems such as chest pain, irregular heartbeats heart failure or high blood pressure and generalised swelling (oedema)
- medicines used to prevent blood clotting e.g. warfarin, dicoumarol or coumarins
- a medicine used to suppress the immune system known as cyclophosphamide
- medicines known as corticosteroids e.g. prednisolone
- the antibiotics called chloramphenicol and rifampicin and antibiotics belonging to a group commonly known as sulphonamides such as sulfafurazole
- voriconazole, fluconazole and ketoconazole which are used to treat fungal infections
- a medicine called lithium which is used to treat mental depression
- monoamine oxidase inhibitors (MAOIs e.g. moclobemide), for which you may carry a warning card and which are used to treat depression
- salicylates, e.g. aspirin used to treat pain
- adrenaline (epinephrine)
- phenylbutazone (a non steroidal anti-inflammatory pain killer) Tolbutamide Tablets with food and alcohol Ask your doctor or pharmacist about your specific dietary requirements. You are advised NOT to drink alcohol with this medicine. Pregnancy and breast-feeding If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor for advice before taking this medicine. Driving and using machines If you experience the symptoms of low blood sugar (hypoglycaemia), especially at the beginning of treatment, you should not drive or operate machinery.
How to take it
Tolbutamide Tablets Always take this medicine exactly as your doctor or pharmacist has told you. Check with your doctor or pharmacist if you are not sure.
These tablets should be taken either with or immediately after the first main meal of the day or in smaller doses throughout the day with meals. Take this medicine for as long as your doctor tells you to. The recommended dose Treatment of previously untreated diabetes: The initial starting dose is two tablets daily, but your doctor may advise you to increase or reduce this until he/she is satisfied that your blood sugar is properly under control. The usual daily dose is 1-3 tablets daily. Change over from other oral hypoglycaemic (e.g. chlorpropamide): You can usually change between different oral hypoglycaemic drugs without a break in treatment. Initially, 1 g (2 tablets) is given. The maintenance dose will depend on response. Change over from insulin: For some cases of non-insulin dependent diabetes, low insulin doses (less than 20 units) can be replaced immediately. With high insulin doses a gradual change is required. Insulin and tolbutamide will be given together, and the insulin dose will be gradually reduced. Taking with biguanides: If you do not achieve adequate control of your diabetes through diet and 2 g (4 tablets) of tolbutamide daily then your doctor may also give you a biguanide drug, such as metformin, to help control your blood sugar levels. Use in the elderly If you are elderly, your doctor will initially prescribe a lower dose. Use in children Tolbutamide Tablets are not for use in children and adolescents. The scoreline is not intended for breaking the tablet. If you take more Tolbutamide Tablets than you should If you realize you have taken more Tolbutamide Tablets than your doctor has recommended (or if someone else has taken some of your Tolbutamide Tablets) contact your doctor right away. If you cannot reach your doctor go to your nearest hospital and take the pack with you. An overdose of Tolbutamide Tablets could cause very low blood sugar level, which may make you feel very ill. Signs of an overdose include feeling or being sick, sweating, fast breathing or heart rate, low blood pressure or drowsiness, odd behaviour, fits or coma. If you forget to take Tolbutamide Tablets If you forget to take a dose, take it as soon as you remember unless it is nearly time for your next dose. Do not take a double dose to make up for the forgotten dose. If you stop taking Tolbutamide Tablets You should continue to take this medicine for as long as your doctor tells you to otherwise your diabetes may not be controlled. If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
Possible side effects
Like all medicines, this medicine can cause side effects, although not everybody gets them. Serious side effects
If the following symptoms occur, please tell your doctor immediately. Symptoms of hypoglycaemia (low blood glucose levels):
- quickening of your heart rate
- sweating
- pallor
- feeling dizzy or hungry
- blurred vision
- inability to concentrate Such symptoms are more common in elderly and debilitated patients. Symptoms of allergic reactions:
- itching and/or rash
- swelling of face, lips, tongue and/or throat
- difficulty in swallowing
- difficulty breathing If you feel very tired, experience unexpected bruising or bleeding, or more infections (e.g. colds and sore throats) than usual please tell your doctor. Your doctor may decide to conduct tests on your blood periodically as a result of these symptoms. Other side effects Other side effects may include:
- headache
- sensitivity to light, which may mean that your skin is more sensitive to the effects of the sun
- anaemia. Tolbutamide may change the number and type of cells in the blood, if you notice an increase in bruising or nose bleeds or in the number of sore throats or infections you are getting, tell your doctor
- low blood sugar (sweating, shaking, double vision, slurred speech, confusion)
- tingling in hands or feet (pins and needles)
- feeling or being sick
- diarrhoea
- constipation
- increased or decreased appetite or weight gain
- skin or eyes appearing yellowish (jaundice), changes in liver function (as seen in blood tests)
- tinnitus
- an intolerance to alcohol causing facial flushing, which may mean that alcohol affects you more than usual or makes you feel unwell. Reporting of side effects If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard By reporting side effects, you can help provide more information on the safety of this medicine.
How to store it
Tolbutamide Tablets Keep this medicine out of the sight and reach of children. Do not store above 25oC. Keep in the original container or package in which they were packed in order to protect from light and moisture. Do not use this medicine after the expiry date that is stated on the carton or bottle after EXP. The expiry date refers to the last day of that month.
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help to protect the environment.
Contents of the pack and other information
What Tolbutamide Tablets contain The active substance is tolbutamide. Each tablet contains 500 mg of tolbutamide. The other ingredients are: starch, povidone, sodium starch glycollate, stearic acid and magnesium stearate. What Tolbutamide Tablets look like and the contents of the pack Tolbutamide Tablets BP 500 mg are round, biconvex white tablets, marked on one side with "T" above a scoreline and "500" below it. They are available in containers of 28, 50 and 500 and blister packs of 28 tablets. Not all pack sizes may be marketed. Marketing Authorisation Holder and Manufacturer Marketing Authorisation Holder Sovereign Medical, Sovereign House, Miles Gray Road, Basildon, Essex, SS14 3FR, UK. Manufacturer Waymade PLC, Sovereign House, Miles Gray Road, Basildon, Essex, SS14 3FR, UK. This leaflet was last revised in: December 2025. PL 06464/0212 Tolbutamide Tablets BP 500 mg To request a copy of this leaflet in Braille, large print or audio format, contact the licence holder at the above address or telephone: 01268 535200 (select option Medical Information) / e-mail: [email protected]
Frequently asked questions about Tolbutamide Tablets BP 500 mg
How do I take Tolbutamide Tablets BP 500 mg?
Tolbutamide Tablets BP 500 mg comes as tablet containing 500mg. Always follow the dose your doctor or pharmacist has given you, and read the leaflet that comes with the medicine.
What is the active substance in Tolbutamide Tablets BP 500 mg?
The active substance in Tolbutamide Tablets BP 500 mg is tolbutamide.
Where does this information come from?
This leaflet reproduces the patient information leaflet approved for Tolbutamide Tablets BP 500 mg, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.
Can I get Tolbutamide Tablets BP 500 mg without a prescription?
Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.
About this leaflet
The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.
- Source: electronic medicines compendium (emc), Datapharm
- Active substance: tolbutamide
- Official document: view the original leaflet on emc →
⚕For healthcare professionals — Summary of Product Characteristics (SmPC)Full SmPC: dosage, interactions, contraindications, warnings+
4.1. Therapeutic indications
For the treatment of non - insulin dependent diabetes in patients who respond inadequately to dietary treatment. It should not be used to replace dietetic therapy in the obese diabetic patient.
4.2. Posology and method of administration
Posology
The tablets may be taken as a single dose with, or immediately after, the first main meal of the day, or as a divided dose for optimum control of blood sugar.
Treatment of previously untreated diabetes: stabilisation can be achieved commencing with 2 tablets (1 g) daily, and adjusting in the light of the patient's individual response. The average daily dose is 1-3 tablets (0.5 – 1.5 g) which can be taken as a single or divided dose as required. In general, patients who do not respond to 4 tablets (2 g) do not respond to higher doses.
Change over from other oral hypoglycaemics: It is possible to freely inter-change hypoglycaemic agents (including chlorpropamide) without a break in treatment, stabilisation can initially be achieved with 2 tablets (1 g) daily, followed by a maintenance dose depending on response.
Combination with biguanides: If adequate control is not achieved with diet and 4 tablets (2 g) of tolbutamide daily, it can often be achieved by combined administration with a biguanide derivative.
Change over from insulin: Some patients with non - insulin dependent diabetes and who are already taking insulin may be changed to tolbutamide. Low insulin doses (less than 20 units) can be replaced immediately. With higher doses a gradual change is advisable by giving insulin and tolbutamide concurrently and gradually reducing the dose of insulin.
Paediatric population: There is insufficient data on the efficacy and safety of tolbutamide in children and adolescents and therefore its use in this age group is not recommended
Elderly: Tolbutamide is particularly suitable for elderly patients as the risk of hypoglycaemia is lower with tolbutamide than other sulfonylureas. However, treatment should be initiated at a lower dose.
Method of administration
Oral administration
4.3. Contraindications
• Hypersensitivity to the active substance(s) or to any of the excipients listed in section 6.1.
• Patients who have, or have ever had, diabetic ketoacidosis.
• Patients with insulin-dependent diabetes mellitus.
• Patients with serious impairment of renal, hepatic, adrenocorticoid or thyroid function.
• Patients in circumstances of unusual stress (eg surgical operations or during pregnancy) when dietary treatment and insulin are essential.
• Patients with porphyria.
• Women who are breast feeding.
4.4. Special warnings and precautions for use
Debilitated, aged or those patients who have difficulty in metabolising tolbutamide may be more liable to hypoglycaemia.
Elderly patients are especially sensitive to sulfonylurea-induced hypoglycaemia and the onset may be insidious and the impaired performance prolonged.
Tolbutamide should not be used as a substitute for dietary treatment in obese patients.
If fever or a sore throat occurs, a white cell count should be performed and repeated after five days as blood abnormalities may develop slowly.
The possibility of thrombocytopenia should be borne in mind and a platelet count performed if indicated.
Patients with mild to moderate renal impairment should start with lower doses and have careful monitoring of the blood glucose levels.
Treatment of patients with G6PD-deficiency with sulfonylurea agents can lead to haemolytic anaemia. Since tolbutamide belongs to the class of sulfonylurea agents, caution should be used in patients with G6PD-deficiency and a non-sulfonylurea alternative should be considered.
4.5. Interaction with other medicinal products and other forms of interaction
The hypoglycaemic effect of tolbutamide may be enhanced by coumarin antico-agulants (e.g. dicoumarol and warfarin), MAOI's, beta-adrenergic blocking agents, sulphonamides, phenylbutazone, chloramphenicol, cyclophosphamide and salicylates or diminished by adrenaline, lithium, rifampicin, corticosteroids, oral contraceptives or thiazide diuretics.
Tolbutamide should not be co-administered with sulfafurazole or coumarins as severe hypoglycaemic reactions have occurred.
Alcohol should be avoided since it may cause a disulfiram-like reaction.
4.6. Fertility, pregnancy and lactation
Pregnancy
Oral hypoglycaemics are not indicated for use by the pregnant diabetic as they will not provide good control of plasma glucose levels in patients that cannot be controlled by diet alone. Insulin should be used to control gestational diabetes if dietary control is not sufficient.
Tolbutamide should not be used during the first trimester of pregnancy. There is some evidence of harmful effects in pregnancy in animals and isolated reports which suggest a hazard in human pregnancy. Placental transfer of tolbutamide may result in prolonged hypoglycaemia in the neonate.
If tolbutamide is to be used in pregnancy, treatment should be changed to insulin at least 4 days prior to delivery to lessen the risk of prolonged hypoglycaemia in the infant.
Breast-feeding
Tolbutamide has been detected in breast milk in small quantities. The effect on the neonate is unknown but there is a theoretical risk of hypoglycaemia. Breast-feeding is best avoided in mothers taking tolbutamide.
4.7. Effects on ability to drive and use machines
While tolbutamide does not cause any adverse effects that may affect a patient's ability to drive or operate machinery, the patient should ensure that their blood glucose levels are adequately controlled before driving or operating machinery.
4.8. Undesirable effects
• Blood and lymphatic system disorders
Blood disorders are rare but may include leukopenia, thrombocytopenia, agranulocytosis, pancytopenia, haemolytic anaemia and aplastic anaemia.
• Immune system disorders
Hypersensitivity reactions may develop, usually within 6 to 8 weeks of starting treatment with tolbutamide. Allergic skin reactions may occur which rarely progress to erythema multiforme, exfoliative dermatitis and fever. Photosensitivity may occur.
• Metabolism and nutritional disorders
Hypoglycaemia and hypoglycaemic symptoms have occasionally been reported when tolbutamide has been administered without due regard to the dietary habits of the patient.
• Nervous system disorders
Paraesthesia and headache have been reported. Patients may become intolerant to alcohol (see section 4.5).
• Ear and labyrinth disorders
Tinnitus has been reported.
• Gastrointestinal disorders
Nausea, vomiting, diarrhoea, anorexia, increased appetite, weight gain and constipation have been reported in patients taking tolbutamide.
• Hepatobiliary disorders
Disturbances in liver function and cholestatic jaundice have been reported.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme; website: www.mhra.gov.uk/yellowcard.
4.9. Overdose
Symptoms
The features are those of hypoglycaemia and include nausea, vomiting, sweating, hyperventilation, tachycardia, hypotension, bizarre behaviour and drowsiness leading to coma with increased muscle tone, hyperreflexia and extensor plantar responses. Convulsions and cerebral oedema may occur.
The duration of the risk of hypoglycaemia varies according to the plasma half-life of the drug. As the half-life of tolbutamide is generally 4-8 hours, a minimum observation period of 24 hours is recommended.
Treatment
1. If the patient is conscious give activated charcoal (50 g) or consider gastric lavage in adults within 1 hour of the overdose, provided the airway can be protected.
2. Correct hypoglycaemia as quickly as possible.
3. If the patient is awake give oral glucose followed by a carbohydrate meal.
4. If the patient is drowsy or unconscious give up to 500 ml 5% or 250 ml 10% dextrose IV. 50ml 50% dextrose IV may be given but is irritant to veins and can cause skin necrosis in cases of extravasation.
5. Glucagon 1-2 mg IM may also be used if IV access is difficult or the patient is combative but its effects are dependent on available glycogen stores.
6. Maintenance treatment with 10% dextrose infusion will be required to prevent persistent hypoglycaemia.
7. Check blood sugar hourly and adjust rate of infusion accordingly.
8. Check urea and electrolytes regularly. Potassium supplements may be necessary.
9. If the patient is persistently hypoglycaemic despite receiving 10% dextrose infusion increase the concentration to 20% dextrose. This is irritant to veins and ideally should be given through a central venous line. Additional potassium may also be required.
10. In cases of severe refractory hypoglycaemia contact NPIS.
💬 Ask about this leaflet
Ask anything about Tolbutamide Tablets BP 500 mg. The assistant answers only from this leaflet — if the leaflet does not cover it, it will say so. It does not give medical advice.
Answers come from the patient leaflet published on the electronic medicines compendium (emc). They are not medical advice. Ask a pharmacist or your GP if you are unsure. For urgent help call NHS 111, or 999 in an emergency.