Tolazamide (Oral)

Tolazamide is often effective in controlling the symptoms of diabetes when used in partnership with improvements in diet and exercise.


Type 2 diabetes is a serious, lifelong condition that results from higher than normal glucose levels in the blood. Although the exact root cause of type 2 diabetes is not known, it is thought that age, background and family history all play a role. The disease is also commonly diagnosed in those over the age of 50 and typically in those with poorer dietary habits and exercise regimes.

Type 2 diabetes occurs when the body does not produce insulin properly. Insulin is needed by the body to help move excess glucose out of our blood and into cells; this enables us to use the glucose for energy. Insulin is essential to keeping blood glucose levels at a manageable level; without it, glucose levels in the blood become too high. If you have type 2 diabetes, you may be at increased risk from heart attacks and stroke.

The good news is that, if diagnosed fairly early, type 2 diabetes can be controlled so that the sufferer can live a normal and healthy life. Treatments commonly prescribed include a mixture of glucose-lowering medication, a cleaner diet and an effective exercise regime. Effective control of type 2 diabetes can also lower your risk of heart disease and stroke.

Tolazamide is a type of medicine that is most commonly used to treat type 2 diabetes. Taken orally, the medicine can control blood sugar levels in the body and can help it to respond more effectively to insulin made by the pancreas.

Tolazamide is not usually prescribed as the sole treatment for type 2 diabetes. It is often part of a holistic treatment package to keep the condition under control, along with a change in diet and increase in exercise levels. It is sometimes prescribed with other medicines commonly used to treat diabetes.

The drug is not used to treat type 1 diabetes.

Conditions treated

Type of medicine

  • Oral

Side effects

This drug is used to alter the levels of glucose in your blood. Therefore, there are various possible side effects that people may experience as a result of this - the most common being hypoglycaemia (while is commonly known as low blood sugar levels). Symptoms of low blood sugar include excessive hunger, weakness, sweating, headache, tremoring, a difficulty in concentrating, increased heart rate, fainting, irritability or even a seizure in the most extreme cases. If symptoms of hypoglycemia are severe, they can be fatal in rare cases, so the advice of a professional must always be sought.

Other typical side effects include vomiting or nausea, upper abdominal fullness and heartburn. These symptoms are usually nothing to worry about, but a doctor should be consulted if these symptoms persist.

Other less common symptoms that may be experienced while taking Tolazamide can be serious. If any of the following are experienced, a doctor should be contacted immediately.

  • Yellowing of the skin or eyes (jaundice)
  • Dark urine
  • Fever
  • Unusual bruising, bleeding or swelling
  • Diarrhea or light coloured, puffy stools
  • Sore throat (sometimes as a result of fever, or otherwise as a standalone symptom)
  • Pain or discomfort in the upper right-hand side of the stomach
  • Skin rash, redness or itchiness
  • Mouth sores, such as ulcers
  • Low sodium levels - with symptoms including confusion, slurred speech, dizziness, vomiting, lack of coordination, headache, severe weakness
  • Heart palpitations
  • Increased urination

Side effects of Tolazamide are not limited to the above; there may be other side effects experienced when taking the drug. Various studies have been undertaken to test the safety of this drug, and should be considered by both doctor and patient when administering a new course of medication. In one such study, it was found that patients taking Tolazamide were more likely to die of heart problems than those treating their diabetes through other means such as improving the diet or through insulin. Therefore you should consider the increased risk before taking the medication; there may be other medications more appropriate for you, depending on your medical history.


The prescribed dose of Tolazamide varies from patient to patient and depends on a number of factors, such as how long the patient has been taking the drug, the severity of his or her diabetes, and the medical history of the patient.

A starter dosage of Tolazamide is usually around 100 to 250 mg for adults over the age of 18. The tablets are taken orally and are usually taken once per day in a single dose. The dose prescribed depends on the blood glucose response and, once the patient has adapted to the medication, it can increase typically to an average of between 250 mg to 500 mg per day. It is recommended that the medication is not taken on an empty stomach - instead, take the oral pill either with breakfast or dinner. It is usually advisable to take the pill at the start or at the end of the day, depending on the side effects that you experience, and how much food you consume in your daily meals.

In the most extreme cases, the daily dose may rise to 1,000 mg per day. For doses prescribed at more than 500 mg per day, two takings are usually advised during the day - one at the start of the day with breakfast and one at the end of it with dinner.

The prescribed dosage of Tolazamide is usually set on the conservative side, particularly in patients that are elderly, malnourished, debilitated or in otherwise poor health. This is because these patients are often more likely to experience hypoglycemic reactions (lowered blood sugar levels) and will be more sensitive to the effects. Lower doses are also prescribed at the beginning of a cycle of Tolazamide for the same reasons, and dosage should be gradually increased to lower the risk of developing hypoglycemia.

There are no recommended dosages for children as there are no studies that currently show the medication is safe for those under 18. The medication is therefore generally administered for adults.

Major drug interactions

There are some drugs that react with others when taken at the same time, impairing their effectiveness or leading to more severe symptoms in patients. This is why doctors will always ask patients whether they are taking any other medication before making a new prescription - and you should always keep a list of those that you are taking. Interactions between drugs can range in severity - from those with mild interactions, to moderate, to major. Major interactions are the most dangerous, and therefore must be avoided at all costs. You can prevent this happening by always being open and honest with your doctor about the other medications that you are taking.

There are known to be 904 drugs that interact in some way with Tolazamide. However, just one drug (with three brand and generic names) is considered to have a major interaction:

  • Gatifloxacin

This drug also has two brand names:

  • Tequin
  • Tequin Teqpaq


The generic drug Gatifloxacin should not be used in patients with diabetes as it commonly affects blood sugar levels. The medicine is known to cause both low blood sugar and high blood sugar levels. In the most severe cases, hyperglycemia and hypoglycemia have been known to cause coma and death. As a result, these drugs should not under any circumstances be taken with other drugs with this same side effect, such as Tolazamide.

Tequin and Tequin Teqpaq are both the same medication as Gatifloxacin, containing the same active ingredients.


There are various warnings for those taking Tolazamide, aside from the aforementioned major interactions.

Food, alcohol and recreational drugs

Other medications are not the only substances that can interact with Tolazamide; food, alcohol and other substances can have a negative impact on the effectiveness of your medication, and can - in some cases - have dangerous side effects. The one other substance that is known to have a major interaction with Tolazamide is alcohol. It is therefore strongly recommended that patients do not consume large amounts of alcohol while taking this medication, as alcohol also commonly adjusts blood glucose levels, and is another cause of both hypoglycemia (low blood sugar levels) and hyperglycemia (high blood sugar levels).

It is particularly wise not to consume alcohol if you have diabetes that is not yet under control, or if you have pancreatitis or nerve damage. You may be able to consume moderate amounts of alcohol while taking the medication, however you should consult your doctor to ensure that you are staying within recommended guidelines for your particular condition. As a general guideline, women can have one drink per day, while men should limit their intake of alcohol to two drinks per day. You should not consume alcohol on an empty stomach, and should always consume it alongside a healthy meal plan. If in doubt about alcohol consumption and diabetes, always consult your doctor.

Other diseases

Aside from substances, other diseases may interact with Tolazamide, so you should always consult your doctor if you have one of the following conditions below. Tolazamide may increase your risk of further developing these conditions and therefore alternative medication is likely to be recommended.

Monitoring of patients taking Tolazamide

Patients taking Tolazamide should be carefully monitored throughout their medication cycle, particularly in the initial stages of taking the drug, and particularly if transferring to the treatment from another drug. This is because overlapping side effects are a possibility, and this can heighten the severity of symptoms experienced.

As Tolazamide is used to treat patients with type 2 diabetes, it is also common for some patients to have previously been treated with insulin. Again, these patients should be monitored closely when taking this medication, as symptoms of side effects may be more severe.


There are currently no studies that have been carried out to determine the safety of the drug in patients under the age of 18. Therefore, extra care and consideration must be taken when administering this treatment to patients of this age range.

Pregnancy and breastfeeding

The drug should not be taken by those that are pregnant or breastfeeding. As yet, there are no studies to show whether Tolazamide can enter the breast milk or whether it could harm a breastfed baby. Likewise, there are no studies to show whether Tolazamide harms unborn babies. However, similar medicines have been shown to cause severe hypoglycemia in newborn babies whose mothers had taken them during the latter stages of their pregnancies.

Missing a dose

If you miss a dose, simply take it as soon as you realise. However, you should always take Tolazamide with food to avoid nausea and other side effects - so wait until your next meal if you have missed a pill. If you miss a dose and find it is very close to your next dose, skip that missed dose entirely. As a warning, you should not take extra doses of Tolazamide to make up for missed tablets.


This medicine must not be taken when the patient is in a state of Ketoacidosis. If this is the case, a doctor must be consulted immediately.


If you take more than the recommended dose of Tolazamide, you must consult a healthcare professional immediately. Overdose of this medication can lead to all of the aforementioned symptoms, with increased severity. Risk blood sugar and coma - even death - is increased in extreme cases of overdose.


Tolazamide should be stored safely and carefully at all times. It will likely come supplied in a sealed container with a lock to prevent children accessing the medication. It should then be stored out of the reach of children, ideally in a secured cabinet or shelf. It is crucial to keep medications such as Tolazamide out of sight of children and pets as, if wrongfully consumed, the medication can be fatal. Always make sure safety caps are locked tightly shut, and never use standard containers to store the medication, as these are often not child- or tamper-proof.

It is recommended that Tolazamide is stored at room temperature (21 degrees centigrade), and also out of direct sunlight or heat sources.

Do not store Tolazamide if you no longer require the medication. If you find you have excess Tolazamide, it is recommended that you dispose of it in a responsible and safe manner - so that pets and children cannot consume the medication. Tolazamide should not be flushed away down drains or toilets, nor should it be disposed of in bins. The safest way to dispose of unwanted Tolazamide tablets is through certified programs designed to take back medication. You can find out about these schemes through a local pharmacist or garbage department. If you do not have access to such a scheme, you can find out about the FSA's recommended methods of disposal.*

If no take-back schemes are available, the FDA recommends disposing of in household trash, unless there are specific instruction for disposal on the manual. It recommends mixing the Tolazamide with another inedible substance such as dirt or used coffee, to avoid human or animal consumption. You should also use a sealed bag, and then place in your household trash can.


While there are various studies that prove Tolazamide to be a highly effective drug in treating the symptoms of type 2 diabetes, its consumption should be closely monitored and treated with caution. The drug has been known to cause a range of both common and rare side effects, and is also proven to be less effective when taken in partnership with major interactions, such as other medication and alcohol. The drug therefore poses a risk to patients that do not communication properly with their doctors; patients should always notify their doctors of any other medications they are taking, their alcohol consumption habits, and any other disease they are suffering from. Side effects should also be monitored closely if they persist, particularly the symptoms of low blood sugar, a common condition to arise from taking the medication.

Tolazamide is most effective when taken as part of a holistic treatment of type two diabetes, with other treatments including an improved exercise regime and a tailored, controlled diet. When taken correctly, Tolazamide can alleviate the uncomfortable everyday symptoms of type 2 diabetes and can also lead to vastly improved longer term health. When used in conjunction with a healthy diet and exercise programme, Tolazamide can help to keep type 2 diabetes under control and can even reverse the disease in the most successful of cases.

Last Reviewed:
December 23, 2017
Last Updated:
April 05, 2018
Content Source: