How does it work?
Glucobay tablets contain the active ingredient acarbose, which is a medicine used to help control blood sugar levels in people with type 2 (non-insulin dependent) diabetes.
Acarbose works by slowing the breakdown and absorption of sugars and starches in the gut. It does this by preventing the action of enzymes in the intestine that would usually break down the sugars and starches that you eat, into molecules that are small enough to be absorbed into the bloodstream. It has most effect on an enzyme called sucrase, which normally breaks down a type of sugar called sucrose.
Acarbose is taken with meals to delay the breakdown of sugars and starches in the gut and slow down their absorption into the blood. It thus prevents the rise in blood sugar that normally occurs following a meal and helps smooth out daily fluctuations in blood sugar.
What is it used for?
Acarbose can be used on its own to treat people with type 2 diabetes whose blood sugar has not been controlled sufficiently by diet, exercise and weight loss alone. It can also be added to treatment with other antidiabetic medicines when these have not proved effective enough.
How do I take it?
- The dose of this medicine that is prescribed and how often it needs to be taken will depend on your blood sugar levels. It is important to follow the instructions given by your doctor. These will be printed on the dispensing label your pharmacist has put on the packet of medicine.
- You usually start off taking the tablets once a day and this is then increased to three times a day with meals.
- The tablets should be chewed with your first mouthful of food, or swallowed whole with a little liquid immediately before eating.
- Your doctor may want you to check your blood sugar level from time to time while you are taking this medicine. Make sure you discuss how to do this and how often with your GP, pharmacist or diabetes specialist.
- This medicine does not cause low blood sugar (hypoglycaemia) itself, however, if it is added to treatment with other antidiabetic medicines there is more chance of your blood sugar falling too low. If you experience low blood sugar while you are taking this medicine, it should be treated with glucose not sucrose. This is because acarbose will delay the absorption of sucrose.
- The most common side effects of this medicine are wind (flatulence), diarrhoea and abdominal pain. These types of side effects are likely to be made worse if you don't stick to the antidiabetic diet that your doctor has advised you to follow. For example, foods containing sucrose often cause abdominal discomfort or diarrhoea in people taking acarbose. These types of side effect are unlikely to be relieved by antacid medicines. If you get these types of side effects despite following your diet and they are distressing, you should consult your doctor.
- This medicine may rarely affect your liver and for this reason, is recommended that your liver function is monitored for the first 6 to 12 months of taking this medicine.
Not to be used in
- Inflammatory bowel disease such as ulcerative colitis or Crohn's disease.
- People with a tendency to suffer from total or partial blockages in the gut.
- People with ulceration in the bowel (colon).
- Conditions such as hernias that may worsen as a result of increased gas formation in the gut.
- Long-term diseases of the gut that are associated with problems digesting or absorbing food.
- Severely decreased liver function.
- Severely decreased kidney function.
- This medicine is not recommended for children and adolescents under 18 years of age, as its safety and effectiveness have not been studied in this age group.
This medicine should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
- This medicine should not normally be used during pregnancy as its safety has not been established. Diabetes mellitus is usually controlled using insulin during pregnancy, because this provides a more stable control of blood sugar. If you get pregnant while taking this medicine, or are planning a pregnancy, you should seek medical advice from your doctor.
- It is not known if this medicine passes into breast milk. It should not be used by women who are breastfeeding. Seek further medical advice from your doctor.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
Very common (affect more than 1 in 10 people)
- Excess gas in the stomach and intestines (flatulence or wind).
Common (affect between 1 in 10 and 1 in 100 people)
- Abdominal pain.
Uncommon (affect between 1 in 100 and 1 in 1000 people)
- Alteration in results of liver function tests.
Rare (affect between 1 in 1000 and 1 in 10,000 people)
- Fluid retention (oedema).
- Inflammation of the liver (hepatitis).
- Decrease in the number of platelets in the blood (thrombocytopenia).
- Allergic reaction, such as rash, redness of the skin, skin eruptions, itching.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to make sure that the combination is safe.
This medicine will enhance the blood sugar lowering effect of other medicines used to treat diabetes, such as insulin, metformin and sulphonylureas such as gliclazide. Your doctor may need to adjust the doses of your other medicines, depending on your blood sugar levels.
Acarbose may reduce the absorption of digoxin from the gut, which may reduce its blood level and make it less effective. If you are taking acarbose with digoxin then your blood level of digoxin should be closely montiored.
Neomycin may enhance the blood sugar lowering effect of acarbose. It may also increase the digestive side effects associated with this medicine, such as wind, stomach cramps and diarrhoea.
If you are taking acarbose with colestyramine your treatment should be monitored, as colestyramine may enhance the effects of acarbose.
The following medicines should not be taken at the same time as acarbose because they can make it less effective:
- charcoal (used to treat heartburn and indigestion)
The following medicines may increase blood glucose levels. If you start treatment with any of these, the doses of your antidiabetic medicines may need adjusting:
- beta-2-agonists, such as salbutamol
- corticosteroids, such as prednisolone
- diuretics, especially thiazide diuretics, eg bendroflumethiazide
- oestrogens and progestogens, such as those found in the contraceptive pill.
The manufacturers of orlistat recommend that acarbose is not used in combination with orlistat.
Other medicines containing the same active ingredient
There are currently no other medicines available in the UK that contain acarbose as the active ingredient.