Decongestant, ephedrine toxicity

Additive sympathomimetic effects may develop when decongestants are administered with other sympathomimetic drug s (see Chap. 22). Use of the nasal decongestants with the MAOIs may cause hypertensive crisis. Use of a decongestant with beta-adrenergic blocking dragp may cause hypertension or bradycardia. When ephedrine is administered with theophylline, the patient is at increased risk for theophylline toxicity. 

The pharmacokinetic and toxicokinetic behavior of any isomer cannot be used to predict that of any other ephedrine isomer. Methamphetamine is a prime example. The d-isomer is a potent, and quite dangerous, central nervous system (CNS) stimulant. The 1-isomer is merely a decongestant. There is a tendency in the literature, particularly in government monographs, to lump together all "ephedrine alkaloids." Doing so is both foolish and misleading, as it implies that the toxicity of all the enantiomers is equivalent, which is clearly not the case. 

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