For relief of cold symptoms,
methylephedrine is considered to be safer than
ephedrine, particularly when used at the predetermined dose. It is often present in various over-the-counter (
OTC) drugs for cold, including paediatric
cough syrups.
CASE SUMMARY: A 52-year-old man presented with worsening dyspnoea and
anorexia for 2 weeks. He was a night shift worker and had been habitually taking large doses of
methylephedrine-containing paediatric
cough syrup for 20 years for sleep averting. On admission, his chest X-ray revealed pulmonary congestion and electrocardiogram showed
sinus tachycardia with left-axis deviation. Echocardiography revealed diffuse hypokinesis with a reduced ejection fraction (EF) of 25%. The
B-type natriuretic peptide level was elevated to 1092 ng/L. Even
after treatment with low-dose
dobutamine and
furosemide in intensive care unit, right-heart catheterization demonstrated a 'wet and cold' profile. Coronary angiography revealed normal coronary arteries. Pathological examination by endomyocardial biopsy revealed cardiomyocyte
hypertrophy with moderate interstitial and replacement
fibrosis. In addition, cardiac magnetic resonance imaging revealed diffuse hypokinesis with mid-wall late
gadolinium enhancement, which suggested
fibrosis. Discontinuation of the
cough syrup and optimal medical treatment with an
angiotensin-converting enzyme inhibitor and a β blocker resulted in improvement in the
heart failure symptoms to New York Class Association Class II. The EF also improved to 50% at 4 months after discharge.
DISCUSSION: