Drug Side Effects
Type 2 diabetes occurs due to muscle, fat and liver cells not being able to use insulin properly. This is a condition called insulin resistance. Thiazolidinediones (TZDs or Glitazones) are a class of drugs that reduce insulin resistance. When cells resist insulin (the hormone produced by the pancreas that helps control blood sugar levels), it means insulin is being produced but isn’t being used effectively in the body. The insulin is unable to deliver sugar to muscle and fat cells, so sugar backs up in the bloodstream instead. Please note, that thiazolidinediones don’t increase insulin production. They increase the effect of the available insulin, reducing insulin resistance at a cellular level.
Thiazolidinediones are used alongside a diet and exercise program and, also, with other medications, for the treatment of T2D.
Thiazolidinedione is not used in the treatment of:
Type 1 diabetes – A condition in which the body is unable to produce insulin and, therefore, cannot control the amount of sugar in the blood.
> Diabetic ketoacidosis – A serious condition that may develop if high blood sugar is not treated.
Rosiglitazone and Pioglitazone are two drugs in this class that have faced a lot of flak due to safety concerns. Both of these drugs work by increasing the body’s sensitivity to insulin.
Often, the side effects of TZDs are anticipated by doctors. But, you need to be aware of them so that you can flag them to your doctor in case they show up.
Thiazolidinediones (Pioglitazone and Rosiglitazone) are available in tablet form. Pioglitazone is usually taken once daily, while Rosiglitazone is usually taken once or twice daily. Both may be taken with or without meals. But, it is important to take the medication at the same time every day.
The most common side effects of Thiazolidinediones that you could face are –
Let us take a look at each of the above common side effects in detail.
The body’s salt balance is determined by your diet and body type and is usually well regulated. Thiazolidinediones can upset this delicate balance and cause the kidneys to retain salt. Since the body needs to keep the corrosive salt diluted, it begins to retain water. This excess water puts pressure on your circulatory system. It seeps out of the blood vessels and accumulates within your body, leading to edema and swelling.
The connection between thiazolidinediones and heart failure has been studied in detail. Prolonged use of thiazolidinediones may lead to a considerable amount of fluid retention. This increases the pressure on the heart and can lead to heart failure. The circulatory system of the body is a closed system, with the amount of fluid determining the blood pressure you feel. If there is too much pressure on the heart, failure is a possibility.
You may notice an increase in your LDL levels after initiating thiazolidinedione therapy. Rosiglitazone has a much more pronounced effect in increasing serum LDL levels than pioglitazone.
(LDL cholesterol is considered the “bad” cholesterol because it is responsible for the generation of plaque – a thick, hard deposit that can block arteries and make them rigid.)
TZDs have not been studied for nutrient depletion effects.
TZDs are normally prescribed only if metformin or other medications, like sulfonylureas, are not tolerated well or fail to lower blood glucose levels sufficiently.
If you have been put on TZDs and want to continue with them, certain dietary supplements that reduce water retention and aid heart health may help to reduce their side effects. These are generally safe but it would be a good idea to keep your medical practitioner involved.
Long term usage of these drugs can have adverse effects, since they deplete certain vital nutrients from the body. Specific nutrient depletions have not been studied for Thiazolidinediones (Pioglitazone / Rosiglitazone.) But, it is quite likely that their action on the body depletes certain vital nutrients, leading to a host of other health complications.
Before taking thiazolidinediones,
Inform your doctor and pharmacist in case you are allergic to TZDs (Pioglitazone/rosiglitazone) or any of the substances in TZD tablets, including other medicinal drugs.
Let your doctor and pharmacist know if you’re taking, or planning to take, the following in the near future:
These might affect how TZDs act in your body and your doctor might have to adjust the dosage accordingly.
Important: Do not breastfeed if you’re taking pioglitazone.
Take the forgotten dose as soon as you remember it. But, if it’s time for the subsequent dose, let the forgotten dose pass and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one.
TZDs should be stored at 25°C (77°F).
Always keep the tablets in a tight, light-resistant container.
Protect the container from moisture and humidity.
Make sure you follow all the exercise and dietary recommendations provided by your healthcare practitioner or dietitian. It is vital to practice a healthy weight-reduction plan, if required, and to exercise often. This will help you keep your diabetes under control and will, also, assist TZDs in acting more effectively.
Gemfibrozil: The maximum recommended dose of pioglitazone is 15mg daily, if used in combination with gemfibrozil, since it significantly increases the concentration of pioglitazone in the blood.
Rifampicin: Rifampicin significantly decreases the concentration of pioglitazone in the blood. Therefore, if rifampicin has been started or stopped during a treatment involving pioglitazone, you may need to make some changes in your treatment regimen. The changes will be based on your clinical response to these drugs used together. But, the maximum recommended daily dose of pioglitazone will not exceed 45 mg.
Gemfibrozil has been shown to increase the concentration of rosiglitazone in blood, while rifampicin decreases its concentration (the same reactions as when they are taken along with pioglitazone.) Therefore, if gemfibrozil or rifampicin has been started or stopped during a treatment involving rosiglitazone, the dosage of rosiglitazone should be changed, based on clinical response.
You should not take pioglitazone if you have –
You should not take rosiglitazone if you –
Severe allergic reactions caused due to ingredients in the rosiglitazone formulation may include:
Ingredients in ACTOS (Pioglitazone) –
Active Ingredient: Pioglitazone hydrochloride
Inactive Ingredients: Lactose monohydrate, hydroxypropyl cellulose, carboxymethyl cellulose calcium and magnesium stearate.
Active Ingredient: Rosiglitazone maleate.
Inactive Ingredients: Hypromellose 2910, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol 3000, sodium starch glycolate, titanium dioxide, triacetin and 1 or more of the following –
Type 2 diabetes is a dietary disorder. If there is a positive change in one’s diet, along with a change in lifestyle and habits, diabetes can be reversed. Changes that include intermittent fasting, yoga, meditation, weight loss and moderate exercise can have a huge impact on diabetics. Having a positive attitude towards life and accepting your diabetic condition will give you a mental outlook that is stable and free of excessive stress.
1. Nutritional Medicine: Alan R. Gaby, M.D., http://www.ncbi.nlm.nih.gov/pubmed/19236215.