Corticosteroids Acetylsalicylic acid

The administration of spironolactone (Aldactone) interferes in the determination of 11-hydroxy corticosteroid by methods that depend on formation of fluorescence in strong sulfuric acid (W15). In 5 patients, the administration of the drug produced as much as a 5-fold increase in the apparent plasma cortisol levels. Aspirin interferes in the determinations of homovanillic acid (HVA) by a fluorometric method. The HVA fluorophore occurs at 320 nm and 420 nm, and acetylsalicylic acid produces fluorescence at 305 to 405 nm (H12). 

There are two major classes of pain medications, nonopioids and opioids. The nonopioids used to treat mild pain include agents such as acetaminophen, both steroid and nonsteroidal antiinflammatory drugs (NSAIDs), and acetylsalicylic acid. Anticonvulsants suppress neuronal firing and are also helpful in neuropathic pain. Antiinflammatory agents (e.g., NSAIDs or corticosteroids) may be particularly helpful when bony involvement occurs and are often used for low-intensity pain. Steroids decrease inflammatory edema and are useful in cases of nerve and spinal cord compression, lymphedema, visceral pain caused by organ enlargement, and bone pain. Finally, short-term corticosteroid therapy may also produce euphoria (thus ameliorating less severe depressions) as well as reverse anorexia. 

Examples of substances that are prone to hydrolysis are acetylsalicylic acid, ampicillin, barbiturates, chloramphenicol, chlordiazepoxide, cocaine, corticosteroid phosphate or succinate esters, proteins, folinic acid, indomethacin, local anaesthetics, paracetamol (acetaminophen), pilocarpine, tropa alkaloids (atropine, scopolamine), xylomethazoline and the antimicrobial preservatives methyl and propyl parahydroxybenzoate. In the field of oncology, melphalan and bendamustine hydrochloride are highly susceptable to hydrolysis with a shelf life of 1.5 h for melphalan and 3.5 h for bendamustine at room temperature. 

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