Aminoglutethimide dosage

The anticoagulant effects of warfarin and acenocoumarol can be markedly reduced by aminoglutethimide. The extent of the reduction appears to be related to the aminoglutethimide dosage. However, in controlled studies, anastrozole and letrozole did not interact with warfarin. 

Aminoglutethimide Reduction possible (111) Unknown Adjust dosage... 

A patient, dependent on dexamethasone due to brain oedema caused by a tumour, deteriorated rapidly, with headache and lethargy, when aminoglutethimide was also given. The problem was solved by withdrawing the aminoglutethimide and temporarily increasing the dexamethasone dosage from 6 to 16 mg daily. ... 

Information is limited but the interaction between dexamethasone and aminoglutethimide is established. The reduction in the serum corticosteroid levels can be enough to reduce or even abolish the effects of corticosteroid replacement therapy or to cause loss of control of a disease condition. This has been successfully accommodated by increasing the dosage of the dexamethasone. Hydrocortisone is routinely used with aminoglutethimide as replacement therapy, and would seem to be a suitable alternative to dexamethasone, where clinically appropriate. Other synthetic corticosteroids are predicted to interact in the same way as dexamethasone, but this needs confirmation. 

It seems probable that aminoglutethimide, a known enzyme inducer, inereases the metabolism of theophylline by the liver, thereby decreasing its levels. The elinieal importanee is uncertain, but it seems likely that the effects of theophylline would be reduced to some extent. Monitor the ef-feets and if neeessary take theophylline levels. Increase the theophylline dosage aeeordingly. 

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