Prescribing Notes
- NICE CG126 covers the management of Stable Angina.
- Nitrates are used in the management of angina pectoris, unstable angina, heart failure and acute myocardial infarction.
- Modified release nitrates should not be given more than once daily as nitrate tolerance will develop. A daily nitrate-free period is necessary to minimise tolerance. The length of the nitrate-free period required varies, and depends on the pharmacokinetic properties of each preparation.
- Therapy should not be discontinued suddenly. Both dosage and frequency should be tapered gradually
- Asymmetric dosing regimens with standard-release nitrate preparations can be confusing to patients and could lead to non-compliance and nitrate tolerance. Consider a switch to modified release preparation.
- Phosphodiesterase type 5 inhibitors (e.g. sildenafil, vardenafil and tadalafil) have been shown to potentiate the hypotensive effects of nitrates (possibly resulting in collapse, unconsciousness and even death), and coadministration with glyceryl trinitrate is therefore contraindicated.
- Nitrates may occasionally aggravate angina in hypertrophic cardiomyopathy and increase intra-ocular pressure in glaucoma