Oral diazoxide

Oral diazoxide (Proglycem) increases serum glucose level by inhibiting insulin release from the beta cells and stimulating release of epinephrine (Adrenalin) from the adrenal medulla. Oral diazoxide is used to treat chronic hypoglycemia caused by hyperinsulinism resulting from islet cell cancer or hyperplasia. It is not for hypoglycemic reactions. 

Diazoxide is a potent vasodilator chemically resembling the thiazides, but it is not a diuretic. Diazoxide can be administered both parenterally and orally. Caution has been stressed when diazoxide is administered as an intravenous bolus into the pulmonary artery because the solution is highly alkaline (pH 11.6) and irritating to vascular tissue (Cotter and Honey, 1980). In one study with chronic oral diazoxide administration (300-600 mg/day), five of seven patients had important side effects including diabetes mellitus, fluid retention, nausea, vomiting, and postural hypertension that required discontinuation of the drug (Wise, 1983). 

B. Oral. Diazoxide (Proglycem), 50-mg capsules, or 50-mg/mL oral suspension. 

Gastrointestinal complaints, nausea and vomiting have been reported. An unusual effect seen on oral diazoxide treatment is the development of hypertrichosis, which occurs in nearly every patient after some months (105, llsCf, 116C, 117 ). The development of extrapyramidal symptoms is mentioned in one article (8 ). Despite the marked increase in serum uric acid levels during diazoxide treatment, there appears to have been no report of the precipitation of acute gout. 

Mussche, M. M., De Broe, M. E., Bel-pairc, F. M., Vermeulen, A. and Ringoir, M. G. (1975) Oral diazoxide contraindicated in severe hypertension with renal failure. Clin. Nephrol, 4, 99.. 

Diazoxide given i.v. causes prominent arteriolar dilation it can be employed in hypertensive crises. After its oral administration, insulin secretion is inhibited. Accordingly, diazoxide can be used in the management of insulin-secreting pancreatic tumors. Both effects are probably due to opening of (ATP-gated) K+ channels. 

This chapter describes four vasodilators in detail. Two of these agents, hydralazine and minoxidil, are effective orally and are used for the chronic treatment of primary hypertension. The other two drugs, diazoxide and sodium nitroprusside, are effective only when administered intravenously. They are generally used in the treatment of hypertensive emergencies or during surgery. 

Azapropazone Diazoxide Heparin Oral hypoglycemics Ticlopidine... 

This class of drugs includes the oral vasodilators, hydralazine and minoxidil, which are used for long-term outpatient therapy of hypertension the parenteral vasodilators, nitroprusside, diazoxide, and fenoldopam, which are used to treat hypertensive emergencies the calcium channel blockers, which are used in both circumstances and the nitrates, which are used mainly in angina (Table 11-3). 

Oral 2.5 mg tablets Vasodilators Used in Hypertension Diazoxide (Hyperstat IV)... 

VASODILATOR ANTI HYPERTENSIVES OESTROGENS Risk of hyperglycaemia when diazoxide is co-administered with combined oral contraceptives Additive effect both drugs have a hyperglycaemic effect Monitor blood glucose closely, particularly with diabetics... 

Because it stimulates the same potassium channel in the pancreatic islet cells as is blocked by sulphonylureas, diazoxide causes hyperglycaemia. This effect renders diazoxide unsuitable for chronic use in h5 ertension, but a useful drug to treat insulinoma. Long-term oral administration causes the same problem of hair growth seen with minoxidil (see below and alopecia ). 

Profound hjrpotension, resulting in renal insufficiency, has been reported in a single patient after the administration of atenolol 100 mg orally (51) however, large doses of furosemide and diazoxide were also given in this case, and this appears more likely to have been a consequence of a drug interaction. 

Diazoxide is administered intravenously for the treatment of hypertension and administered orally for the treatment of hypoglycemia. 

Diazoxide is therapeutically administered either intravenously or orally. 

Diazoxide is well absorbed orally. It is distributed to the plasma where it is highly bound (>90%) to the plasma proteins. It readily crosses both the placental and blood brain barriers. The volume of distribution is 180 ml kg The half-life of elimination for diazoxide is 15-30 h. Approximately 20-50% of diazoxide is eliminated unchanged by the kidney, with the remainder being metabolized by the liver to 3-carboxy and 3-hydroxymethyl derivatives. 

Diazoxide, is used orally as an antihypoglycemic agent. Used parenterally, it acts as an arterial vasodilator and acts to selectively relax arterial smooth muscle. Because venous capacitance is not affected, systolic pressure is reduced more than diastolic pressure, and pulse pressure is reduced. 

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