Headache, dizziness, fatigue, palpitations, orthostatic hypotension, and flushing may occur at the beginning of treatment. These reactions are usually controlled by lowering the dose; and tend to decline with time.
Adverse reactions are listed below by system organ class and frequency. Frequencies are defined as follows: very common (≥ 1/10), common (≥ 1/100 to < 1/10), uncommon (≥ 1/1,000 to < 1/100), rare (≥ 1/10,000 to < 1/1,000), very rare (< 1/100,000), not known (cannot be estimated from the available data).
Immune system disorders
Uncommon: allergic skin reaction (e.g. rash) which may sometimes be severe.
Nervous system disorders
Very common: headache. The incidence of headache diminishes gradually with time and continued use.
Cardiac disorders
Not known: hypoxaemia. During treatment with these tablets, a temporary hypoxaemia may occur due to a relative redistribution of the blood flow in hypoventilated alveolar areas. Particularly in patients with coronary artery disease this may lead to a myocardial hypoxia.
Vascular disorders
Common: hypotension. At start of therapy or when the dosage is increased, hypotension and/or light-headedness on standing may occur. These symptoms may be associated with dizziness, drowsiness, reflex tachycardia, and a feeling of weakness.
Uncommon: flushing.
Collapse may occur (sometimes accompanied by bradyarrhythmia and syncope). Severe hypotension may lead to enhanced angina symptoms.
Not known: severe hypotensive responses have been reported for organic nitrates and include nausea, vomiting, restlessness, pallor and excessive perspiration.
Gastrointestinal disorders and administration site conditions
Uncommon: nausea, vomiting
Not known: a few reports of heartburn, most likely due to a nitrate induced sphincter relaxation have been recorded.
Skin and subcutaneous tissue disorders
Very rare: Stevens-Johnson syndrome, angioedema
Not known: exfoliative dermatitis.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.