Glipizide (Oral)

Glipizide is a drug that is used to treat high blood sugar in patients with type 2 diabetes.


Glipizide is sold in the US under the brand names Glucotrol XL and Glucotrol. It is a prescription only drug that comes in the form of tablets and extended release tablets.

Glipizide is one of a family of medicines called sulfonylureas. It is used to treat the high levels of blood sugar that are caused in type 2 diabetes mellitus patients. In patients with this condition, the body cannot process excess sugar properly, allowing it to remain circulating around in the bloodstream, rather than being stored. If this problem becomes chronic, serious health problems and complications can arise in the future.

In conjunction with a correctly balanced and managed diet, glipizide works by stimulating the pancreas to release insulin into the bloodstream. This has the effect of prompting the body to store the sugar that is contained in the patient's blood, lowering blood sugar levels.

However, it should be understood by patients that, although glipizide is very effective in treating high blood sugar, it will not provide a complete cure for your diabetes.

Conditions treated

  • High blood sugar in diabetes mellitus sufferers

Type of medicine

  • Sulfonylureas

Side effects

In addition to the effects that it is intended to bring about, some medication can cause undesirable or unforeseen side effects. If these effects do manifest themselves, you may need further medical treatment to manage them.

If you notice any of the effects that are mentioned in the list below, you must check with your GP:

  • Yellow eyes or skin
  • Wheezing
  • Vomiting of blood or material resembling coffee grounds
  • Vocal changes
  • Feelings of unusual tiredness or weakness
  • Unusual bleeding or bruising
  • Unpleasant odor of the breath
  • Trouble with swallowing
  • Tightness of the chest
  • Swollen, tender glands in the neck
  • Swollen joints
  • Swelling of the hands, ankles or face
  • Sweating
  • Stupor
  • White spots, sores, or ulcers on the lips or in the mouth
  • Slurred speech
  • Thinness of the skin
  • Shortness of breath
  • Shakiness
  • Severe stomach pains
  • Sensitivity to sunlight
  • Seizures
  • Runny nose
  • Pain, redness, or swelling of the eyelid, eye, or inner lining of the eyelid
  • Reddening of the face, arms, neck, and occasionally of the upper chest
  • Rash
  • Unexpected rapid weight gain
  • Increase in urine volume or frequency
  • Pounding in the ears
  • Red pinpoint dots on the skin
  • Joint pain
  • Eye pain
  • Nosebleeds
  • Nightmares
  • Nervousness
  • Nausea
  • Muscle twitching
  • Muscle pain or stiffness
  • Muscle aching or cramping
  • Side or lower back pain
  • Loss of appetite
  • Light-colored stools
  • Lethargy
  • Leg cramps
  • Itching
  • Irritability
  • Indigestion
  • Increased thirst
  • Increased hunger
  • Hostility
  • Hoarseness
  • High fever
  • Heartburn
  • Headache
  • General feelings of weakness or tiredness
  • General body swelling
  • Fluid-filled skin blisters
  • Fever
  • Feeling of warmth
  • Rapid, slow, or irregular heartbeat
  • Fainting
  • Excessive tearing
  • Dryness or soreness of the throat
  • Dizziness
  • Difficulty moving
  • Difficult or painful urination
  • Difficult or labored breathing
  • Diarrhea
  • Depression
  • Decreased vision or other visual interruption
  • Decreased urine output
  • Dark urine
  • Cough
  • Cool, pale skin
  • Convulsions
  • Constipation
  • Congestion
  • Confusion
  • Coma
  • Cold sweats
  • Clay-colored stools
  • Chills
  • Chest pain
  • Itching, burning, or dry eyes
  • Sensations of crawling, burning, itching, prickling, numbness, "pins and needles", or tingling
  • Body aches or pains
  • Blurred vision
  • Black or bloody stools
  • Blood in the urine or stools
  • Bloating
  • Bleeding gums
  • Back or leg pain
  • Anxiety
  • Agitation
  • Abdominal or stomach pains

There are some side effects that may be caused by glipizide that often go away without the need for medical intervention. These effects usually just disappear as your body gets used to the new drug. You GP may be able to suggest ways in which you can prevent or manage these effects. If you are affected by any of the following side effects, have a chat with your GP:

  • Weight loss
  • Walking strangely
  • Unusually warm skin
  • Insomnia
  • Stuffy nose
  • Sneezing
  • Sleeplessness
  • Sleepiness or unusual drowsiness
  • Skin rash, scaly, encrusted and oozing
  • Severe sunburn
  • Sensation of spinning
  • Passing more gas than usual
  • Pain
  • Muscle tension or tightness
  • Muscle stiffness
  • Mood or mental changes
  • Loss in sexual performance
  • Loss of libido
  • Indigestion
  • Increased sensitivity of the skin to sunlight
  • Welts or hives
  • Severe, throbbing headache
  • Full feeling
  • Flushing or redness of the skin
  • Feeling of constant movement of self or surroundings
  • Excessive muscle tone
  • Excess gas in the intestines or stomach
  • Dizziness or lightheadedness
  • Belching
  • Acid or sour stomach

It should be noted by patients that these are not the only side effects that have been reported by patients who are taking glipizide. If you experience any effects that are not included in this guide, you should check with your GP.


When you are prescribed glipizide as part of your diabetes treatment program, you will also be given a special dietary plan. It is important that you stick rigidly to this plan, as your medication will not work properly if you deviate from it. You must also exercise regularly and test your urine and blood sugar levels as you have been directed to by your GP.

When you are given your prescription for glipizide, you will also be given a patient information leaflet. Be sure to read all the information contained therein and ask your GP if there is anything you do not understand.

When taking the extended-release tablet version of the medication, you must swallow it whole. You should not crush, chew, suck, or split the tablet. You may also notice that the extended-release tablets may pass into your stools. This will only happen after your body has absorbed all the drug. This should not be cause for concern and is perfectly normal.

The dose of glipizide will not be the same for every patient who is taking it. You should take your tablets as you have been directed by your GP or as per the instructions given on the dispensary product label. The information that follows is based on the average dose for this drug. If your prescribed dose is at variance with this, do not alter it unless you are told to by your GP.

The dose of glipizide that you are told to take will depend on the strength of the tablets. The quantity of daily doses, their frequency, and the total duration of your course of treatment will depend on the health condition that you are taking the medicine for.

Extended-release tablets for type 2 diabetes:

  • Adults: Initially, take 5 mg once daily at breakfast time. The total dose is not generally over 20 mg daily, and your GP will alter your dose if necessary.
  • Children: Your child's GP will give you instructions on the dose and use of this medication.

Tablets for type 2 diabetes:

  • Adults: Initially, take 5 mg once daily at least half an hour before you have you breakfast. The total dose is not generally over 40 mg daily, and your GP will alter your dose if necessary.
  • Children: Your child's GP will give you instructions on the dose and use of this medication.

If you forget to take your daily dose of this drug, you should take it immediately. However, if your next dose is due, leave it out and go back to your usual schedule. Do not take a double dose.

Do not share your medication with anyone else.

If you do not think that your condition is improving, or if you begin to feel worse after you start your course of glipizide, you must check with your GP.


Drug interactions

Some medication should never be used at the same time as glipizide as this could cause an interaction to take place. However, sometimes it may be appropriate to your treatment for you to take two medicines at the same time, even though there may be an interaction. Your GP will advise you on how to prevent or manage any interactions that could happen, or may change the dose of one of your drugs.

Taking glipizide with any of the drugs listed below is not generally a good idea, but it may be necessary in some patients. If you are told to take both medications together, your GP may change the frequency of use or dose of one or both drugs:

  • Tosufloxacin
  • Thioctic Acid
  • Sparfloxacin
  • Rufloxacin
  • Prulifloxacin
  • Pefloxacin
  • Pazufloxacin
  • Pasireotide
  • Ofloxacin
  • Octreotide
  • Norfloxacin
  • Nadifloxacin
  • Moxifloxacin
  • Metreleptin
  • Lomefloxacin
  • Lixisenatide
  • Levofloxacin
  • Lanreotide
  • Gemifloxacin
  • Gatifloxacin
  • Flumequine
  • Fleroxacin
  • Entacapone
  • Enoxacin
  • Dulaglutide
  • Disopyramide
  • Ciprofloxacin
  • Ceritinib
  • Besifloxacin
  • Balofloxacin
  • Aspirin
  • Acarbose

Using glipizide with any of the drugs listed below could cause an increased danger of serious side effects occurring. However, this could be the best option for your treatment. If you are told to take both medicines, you may be instructed to change the dose or frequency of one or both of them:

  • Voriconazole
  • Tranylcypromine
  • Timolol
  • Sotalol
  • Selegiline
  • Safinamide
  • Rasagiline
  • Ranitidine
  • Psyllium
  • Propranolol
  • Procarbazine
  • Practolol
  • Pindolol
  • Phenelzine
  • Penbutolol
  • Oxprenolol
  • Nialamide
  • Nebivolol
  • Nadolol
  • Moclobemide
  • Metoprolol
  • Metipranolol
  • Methylene Blue
  • Linezolid
  • Levobunolol
  • Labetalol
  • Isocarboxazid
  • Iproniazid
  • Glucomannan
  • Furazolidone
  • Fenugreek
  • Esmolol
  • Cyclosporine
  • Colesevelam
  • Clarithromycin
  • Cimetidine
  • Celiprolol
  • Carvedilol
  • Carteolol
  • Bitter Melon
  • Bisoprolol
  • Betaxolol
  • Atenolol
  • Acebutolol

Other interactions

You should not use certain drugs when you are eating or when you are eating particular foodstuffs, as this could cause an interaction. If you smoke or drink alcohol whilst using certain drugs, this can also cause interactions. Discuss this aspect of your medication regimen with your GP before you begin your course of treatment.

Note that you should not consume ethanol while you are using glipizide.

Medical interactions

Some existing medical conditions can affect how a medicine works. You must have a full discussion of your medical history with your GP before you begin using glipizide.

It should be noted that patients with any of the medical conditions mentioned below are more prone to developing low blood sugar while taking glipizide:

  • Weakened physical condition
  • Undernourished condition
  • Underactive pituitary gland
  • Underactive adrenal glands
  • Any other condition that causes low blood sugar
  • Alcohol intoxication

Glipizide should not be given to patients who have type I diabetes, or diabetic ketoacidosis.

The following conditions can cause temporary complications with controlling blood sugar. In this case, your GP may decide to temporarily treat you with insulin:

  • Trauma
  • Surgery
  • Infection
  • Fever

Glipizide can cause hemolytic anemia in some patients who have the enzyme disorder glucose 6-phosphate dehydrogenase (G6PD).

The use of this medication in patients with blood vessel or heart diseases can make these conditions worse.

It should be noted that higher than expected levels of glipizide may occur in patients who have kidney or liver disorders. This could cause serious complications in these patients.

It should be noted that the extended-release version of this medication should be used with caution in people who have blocked or narrow intestines, stomach, or esophagus, as it could cause an obstruction.


Before you begin using any medication, you should consider the risks versus the benefits of doing so. Your GP will discuss this aspect of your care with you.


Be sure to tell your GP if you have ever noticed any odd reactions to glipizide or to any other prescription or over the counter drug before. Also tell your GP if you have known allergies to food colors, preservatives, certain food groups, or animal by-products. Check the product label carefully to make sure that it does not contain anything that could trigger a bad reaction.


Glipizide is not known to cause any danger to pediatric patients. However, if you have any concerns in this regards, you should discuss your child's treatment with your doctor.


Although there are no known geriatric-specific problems concerning the use of glipizide, it should be borne in mind that elderly people are more likely to suffer from kidney, liver or heart problems that are age-related. Caution should therefore be exercised when calculating the dose of this medication for this group of patients.

Pregnancy and breastfeeding

There is no evidence to suggest that pregnant women should not use glipizide or that it presents any danger to the unborn baby. Similarly, glipizide is not known to adversely affect nursing infants. However, pregnant or lactating women should discuss this aspect of their treatment with their GP or midwife before beginning a course of treatment with this drug.

Medical complications

Throughout the course of your treatment with glipizide you must make regular visits to your GP for check-ups to ensure that the drug is working as expected and to discuss any side effects that may have occurred. Your GP may also ask you to have urine and blood tests as part of this monitoring process.

It should be noted that consuming alcohol can lower your blood sugar. This could affect your dosage of glipizide, and you should therefore discuss your use of alcohol with your GP.

When you are diagnosed with type 2 diabetes, you may wish to have special counseling to gain a clearer understanding about how to manage your condition through diet and exercise, as well as medication. If you are intending to try for a baby, you should also discuss this with your counsellor, as problems can occur in diabetic patients during pregnancy.

When you travel away from home, be sure to keep your medical history and a recent prescription for glipizide with you. Try to keep your meal times as close as possible to the norm when traveling in different time zones to ensure that your medication is not adversely affected.

Just in case there is an emergency, it is a good idea to wear a medical identification bracelet or pendant, or carry a medical ID card with you at all times, stating that you are diabetic and listing all your medications.

You must tell your GP straight away if you begin to experience pains in your chest, arms, back, neck, or jaw; nausea; shortness of breath; vomiting; or sweating while you are taking glipizide. These can all indicate a heart attack or some other serious heart problem.

This medicine can cause low blood sugar (hypoglycemia). This can also happen if you miss a meal or snack, take more exercise than you usually do, drink alcohol, are unable to eat because you are nauseous or vomiting, or take certain other medications. If low blood sugar is not treated quickly, there is a risk that you could become unconscious. The red flags that tell you of an impending hypoglycemic episode vary between patients, so it is very important that you learn to recognize your own unique symptoms.

Signs of low blood sugar include the following:

  • Anxiety
  • Blurred vision
  • Behavioral changes
  • Appearance of being inebriated
  • Blurred vision
  • Confusion
  • Cold sweats
  • Pale skin
  • Cognitive difficulties
  • Feeling drowsy
  • Excessive hunger
  • Rapid heartbeat
  • Persistent headache
  • Nausea
  • Feeling nervous
  • Nightmares
  • Disturbed sleep
  • Shakiness
  • Slurring of speech
  • Feeling unusually weak or tired

If you think that your blood sugar is dropping too low, you should eat glucose gel or tablets, sugar cubes, honey, corn syrup, fruit juice, sugar dissolved in water, or non-diet soft drinks. You should also have a glucagon kit available, together with a needle or syringe, and be sure that you or a member of your family is confident in its use. Glucagon should be used in emergencies, including the treatment of seizures.

While you are using glipizide, you must not use other medicines, unless you have previously discussed their use with your GP. This includes non-prescription drugs, herbal remedies, and vitamin supplements.


You should keep your supply of glipizide tablets in a sealed container at room temperature. Choose a location that is not close to sources of heat or direct sunlight. Do not freeze the medicine.

Put the tablets well out of reach of pets and children. If a pet does consume any of your glipizide tablets, you should contact your emergency vet right away.

If you no longer require your tablets or if they have become out-of-date, you must dispose of them correctly. Your GP or pharmacist will advise you on the safest way to get rid of unwanted medications.


Glipizide is a drug that is used to treat excess blood sugar in people who have type 2 diabetes mellitus. The medication is a sulfonylurea. It works by causing the patient's pancreas to secrete insulin, effectively triggering the body to store the excess sugar in the bloodstream and thus lowering blood sugar levels. The drug is used in conjunction with a correct diet and exercise regime. This medication cannot cure type 2 diabetes, but it does help to control some of the symptoms.

This drug does cause a number of potentially serious side effects in patients with certain existing health conditions as well as diabetes mellitus. There is also a long list of medicines that cannot be taken at the same time as glipizide, as they could cause notable interactions. You must discuss your medical history fully with your GP before you start using this drug. Throughout your course of treatment, you will be required to attend your GP clinic for regular check-ups to make sure that your body is responding to the drug as desired and to check for any side effects.