Tolbutamide

Brand names

• Apo-Tolbutamide
• Mobenol
• Novo-Butamide
• Oramide
• Orinase
• Orinase Diagnostic
• SK-Tolbutamide

Usage

To help control blood sugar in patients with non-insulin-dependent (type 2) diabetes.

How it works

Tolbutamide stimulates insulin release from the pancreas and reduces glucose output by the liver.

Side effects

Serious

Seizures, fainting, low blood sugar causing anxious feeling, blurred vision, cold sweats, confusion, drowsiness, excessive hunger, fast heartbeat, headache, nausea, nervousness, restless sleep, shortness of breath, unusual weight gain, unusual bleeding or bruising. Other serious but less common side effects include bone marrow suppression, hemolytic anemia, and elevation of liver associated enzymes; these problems can be detected by your doctor.

Common

Changes in taste, constipation or diarrhea, more frequent urination, headache, heartburn, increased or decreased appetite, nausea, stomach pain or fullness, vomiting.

Less common

Increased sensitivity of skin to the sun.

Possible interactions

Other medicaments:

The following medicaments may increase the effects of tolbutamide:

• acarbose (Precose).
• aspirin and other salicylates.
• chloramphenicol (Chloromycetin).
• cimetidine (Tagamet).
• cisapride (Propulsid).
• clofibrate (Atromid-S).
• clopidogrel (Plavix).
• cotrimoxazole (Bactrim, others).
• erythromycin / sulfisoxazole.
• fenfluramine (Pondimin).
• fluconazole (Diflucan).
• itraconazole (Sporanox).
• ketoconazole (Nizoral).
• monoamine oxidase (MAO) type A inhibitors.
• nonsteroidal anti-inflammatory medicaments (NSAIDs).
• phenylbutazone (Butazolidin).
• ranitidine (Zantac).
• sulfonamide medicaments.
• trimethoprim (Septra, others).
• valproic acid (Depakene).

The following medicaments may decrease the effects of tolbutamide:



• beta blockers.
• bumetanide (Bumex).
• corticosteroids.
• diazoxide (Proglycem).
• ethacrynic acid (Edecrin).
• furosemide (Lasix).
• phenytoin (Dilantin).
• rifampin (Rifadin, Rimactane).
• thiazide diuretics.
• thyroid hormones.

Tolbutamide taken concurrently with:



• colestipol (Colestid) can result in decreased colestipol response.
• digoxin may result in increased risk of digoxin toxicity.
• insulin will result in additive lowering of the blood sugar.
• ritonavir (Norvir) may lead to tolbutamide blood level changes.
• sulfonamides may result in a greater than expected effect of tolbutamide-caution against hypoglycemia is advised, along with consideration for lower tolbutamide doses while the medicines are combined.

Foods:

Follow the diabetic diet prescribed by your physician.

Herbal medicines or minerals:

Using chromium may change the way your body is able to use sugar.  DHEA may change sensitivity to insulin or insulin resistance. Hawthorn, ginger, garlic, ginseng and licorice, nettle and yohimbe may change blood sugar. Since this may require adjustment of hypoglycemic medicine dosing, talk to your doctor before combing any of these herbal medicines with this medicine.

Alcohol:

Alcohol can exaggerate this medicament's hypoglycemic effect. This medicament infrequently causes a marked intolerance of alcohol resulting in a disulfiramlike reaction: facial flushing, sweating, palpitation.

Tobacco smoking:

Decreased tolbutamide blood levels are found in smokers.

Exposure to sun:

Use caution-some medicaments of this class can cause photosensitivity

Occurrence of unrelated illness:

Acute infections, illnesses causing vomiting or diarrhea, serious injuries and surgical procedures can interfere with diabetic control and may require insulin. If any of these conditions occur, call your doctor promptly.

Discontinuation:

Because of the possibility of secondary failure, it is advisable to evaluate the continued benefit of this medicament every 6 months.