Pharmacotherapy is inevitably associated with the risk of drug-related complications; the most controversial is the effect of pseudoephedrine on blood pressure and its consequences. Some literature data suggest that oral sympathomimetic drugs may dangerously increase blood pressure, while others reassure that the danger is exaggerated. One meta-analysis of randomised controlled trials showed that PSE at the recommended doses had no effect on systolic and diastolic blood pressure in healthy or controlled hypertensive patients. Systolic blood pressure increases by an average of 1 mm Hg and the heart rate increases by three beats per minute. Only about 3% of the analysed patients had pressures above 140/90 mm Hg
[15]. During the use of pseudoephedrine preparations, reported cases include an acute coronary syndrome in a patient who performed hard physical work and smoked for 30 years; a myocardial infarction, hypertensive crisis and NSTEMI (Non-ST-Segment Elevation Myocardial Infarction) without ST segment elevation after taking the drug in the extended-release form by an 87-year-old man with history of mild dementia, glaucoma and atrial fibrillation; as well as an increased blood pressure of 220/140 mm Hg, hyperglycaemia, haemorrhagic stroke, strong, reversible spasm of blood vessels and tachycardia in a driver working at night, a nicotine addict and concomitant drug user for more than 20 years
[7][15][16][17][18]. The effect of pseudoephedrine may induce non-convulsive epileptic states in predisposed individuals with pre-existing neurological disorders
[7][19]. The risk of complications increases in patients with impaired renal and hepatic function. Unusual behaviour and myoclonic convulsions were observed in a 64-year-old man suffering from renal failure, who took 240 mg of PSE daily to treat rhinitis
[7]. Severe agitation and disorientation can be expected in patients with phenylketonuria due to a disturbed metabolism of catecholamines
[4]. Adverse effects of PSE can occur with both oral and intranasal administration after a single dose or after prolonged (5 days) treatment, without affecting the dose and irrespective of the vascular condition and age. A 2003 French study analysed adverse events with intranasal decongestants reported to regional pharmacovigilance centres by healthcare professionals. There were 22 episodes of arterial hypertension, 15 cases of convulsions and 4 cases of stroke after oral administration of drugs containing pseudoephedrine
[20]. It can also induce ischemic colitis when used for as little as 3 days or up to 2 years, in a dose range of 60 to 900 mg/day
[21]. Less common adverse effects are skin reactions—cases of scarlet fever-like rash, erythematous spots, skin exfoliation of the palms and soles of the feet, and Baboon syndrome, clinically manifested by a rash mainly on the buttocks and within the larger folds of skin, have been reported
[22][23]. When used in therapeutic doses, PSE may be responsible, especially in children, for the occurrence of pain and dizziness, increased heart rate, excessive agitation, insomnia and hallucinations
[4]. “Parasitic” hallucinoses (attacking spiders and insects) have been observed in children after taking an OTC (over-the-counter) drug containing pseudoephedrine and triprolidine to treat inflammation of the nasal mucosa
[4][7]. In 2007 Wingert et al. detected pseudoephedrine in a postmortem analysis of 13 unexpected deaths of children under 2 years of age taking cold medications in the Philadelphia region. Similar observations were made in 2008 by Rimsza and Newberry, who reviewed case files of unexpected deaths of children taking cold medications. PSE preparations should not be used in patients before the age of 12, and according to the French Society of Otorhinolaryngology, until the age of 15
[20]. On the pharmaceutical market, however, there are preparations allowing their administration to younger patients, e.g., from 7 years of age. The addictive potential of PSE is confirmed by the case of a 37-year-old woman who abused it for its euphoric effect, increasing the doses over five years, using 3000–4500 mg daily. Sudden discontinuation of the drug resulted in depressed mood, visual hallucinations and a feeling of fatigue
[7].