Thiazides Chlorpropamide

THIAZIDES CHLORPROPAMIDE Risk of hyponatraemia when chlorpropamide is given to a patient taking both potassiumsparing diuretics/aldosterone antagonists and thiazides Additive effect chlorpropamide enhances ADH secretion Monitor serum sodium regularly... 

Allergic vasculitis e.g. sulphonamides, NSAIDs, thiazides, chlorpropamide, phenytoin, penicillin, retinoids... 

Nephrogenic diabetes insipidus is due to resistance to action of vasopressin, and therefore DDAVP is not indicated, but some benefit may be gained by using thiazide diuretics or chlorpropamide. The syndrome of inappropriate antidiuretic hormone (SIADH) can be treated by using the antibiotic derivative demeclocycline to induce a state of vasopressin resistance and partial nephrogenic diabetes insipidus. 

Hyponatmemia is common with the thiazides and to a lesser extent with the loop diuretics. It occurs when the osmolality of the urine persistently exceeds that of the fluid intake and is associated with the inability of the kidney to produce a dilute urine. It is not usually severe. The origin is multifactorial and involves unrestricted fluid intake and increased ADH activity due to volume depletion. Co-administration of dipsogenic drugs, such as the tricyclic antidepressants, or those with ADH-like effects, such as chlorpropamide, can exacerbate the problem. There are rare occasions when hyponatraemia (Nan- concentration less than 100 mmol-L-l) can be of sufficient severity to be life threatening. 

The use of fixed combination of a thiazide and a potassium-sparing drug, often Moduretic (hydrochlorothiazide 50 mg with amiloride 5 mg), has been consistently implicated in diuretic-induced hyponatremia. Treatment with chlorpropamide (200-800 mg/day) along with Moduretic has precipitated hyponatremia in several cases (96). Simultaneous use of Moduretic with trimethoprim has also been reported to increase the risk (97). The mechanism appears to be impairment of the clearance of free water, resulting in dilutional hyponatremia. Whether... 

Common drug causes of lichenoid eruptions are antimalarials, beta-blockers, chlorpropamide, furosemide, gold, methyldopa, phenothiazines, quinidine, thiazides, and tolazamide. 

Hyponatremia (serum sodium <129 mEq/L) is reportedly associated with tolbutamide, but it is most common with chlorpropamide and occurs in as many as 5% of individuals treated. An increase in antidiuretic hormone secretion is the mechanism for hyponatremia. Risk factors include age >60 years, female gender, and concomitant use of thiazide diuretics. 

The drug most commonly used in clinical practice that can produce immune thrombocytopenic purpura is heparin. Other examples are sulfonamides, thiazide diuretics, chlorpropamide, quinidine, and gold. These types of immune thrombocytopenic purpura are reversed when the drug is withdrawn. Molecular mechanisms for the formation of specific drug-dependent antibodies appear to be very similar. The glycoproteins on the platelet surface interact with the drugs to form neo-epitopes. Subsequent... 

Not understood. One study suggested that the hyperglycaemia is due to the inhibition of insulin release by the pancreas." Another suggestion is that the peripheral action of insulin is affected in some way. " There is also evidence that the effects may be related in part to potassium depletion." The hyponatraemia appears to be due to the additive sodium-losing effects of chlorpropamide, the thiazide and amiloride. Obese patients may be more sensitive to the effects of hydrochlorothiazide on insulin metabolism."... 

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