Syndrome of inappropriate antidiuresis in doxylamine overdose.

Doxylamine succinate, an H(1)-antihistamine drug, is commonly used as sleep-inducing agent as well as therapy for nausea and vomiting in pregnancy. At usual doses, it may cause impairment of cognitive and psychomotor performance, anticholinergic effects, agitation and postural hypotension. Besides, since this drug is frequently involved in either accidental or intentional overdoses, it seems relevant to bear in mind other possible toxic effects. We report a case of acute severe hyponatremia in the setting of a syndrome of inappropriate antidiuresis (SIAD), an apparent new adverse effect linked to doxylamine overdose. The Naranjo adverse drug reaction probability scale indicated a probable relationship between doxylamine intake and SIAD development. SIAD may be considered as a potential, serious adverse reaction of doxylamine overdose. Clinicians should consider this aetiological possibility when attending patients suffering from hyponatremia.

Pulmonary arterial hypertension associated with neurofibromatosis type 1.

The authors report a case of severe pulmonary arterial hypertension (PAH) in a 75-year-old woman who had received a diagnosis of neurofibromatosis type 1 (NF1) 23 years before. She presented with progressive dyspnoea and recurrent syncope. Even though the patient initially improved after starting supportive and specific treatment for PAH, she then deteriorated and died from respiratory failure 11 months after the diagnosis of PAH. Prompt recognition of such an unusual association between PAH and NF1 and appropriate therapeutic intervention could ameliorate quality of life and prolong survival in this patient population.