What side effects can phenylephrine in Covonia All-in-One Chesty Cough, Cold & Flu Relief Oral Solution cause?

Phenylephrine in Covonia All-in-One Chesty Cough, Cold & Flu Relief Oral Solution rarely causes side effects at normal doses, including hypertension, palpitations (tachycardia), headache, dizziness, vomiting, diarrhoea and insomnia; urinary retention is also reported (frequency unknown), more likely in men with an enlarged prostate.