From the FDA Drug Label
Daily headaches sometimes accompany treatment with nitroglycerin. In patients who get these headaches, the headaches are a marker of the activity of the drug Patients should resist the temptation to avoid headaches by altering the schedule of their treatment with nitroglycerin, since loss of headache is likely to be associated with simultaneous loss of antianginal efficacy. Headache, which may be severe, is the most commonly reported side effect. Headache may be recurrent with each daily dose, especially at higher doses
The FDA drug label does not provide guidance on how to alleviate headaches caused by nitroglycerin paste. It only mentions that headaches are a common side effect and a marker of the drug's activity, and that patients should not alter their treatment schedule to avoid headaches, as this may reduce the drug's antianginal efficacy 1 1.
From the Research
Introduction to Nitroglycerin-Induced Headaches
Nitroglycerin, commonly used to treat angina, can cause headaches as a side effect. These headaches can be debilitating and affect the quality of life of patients.
Types of Headaches Caused by Nitroglycerin
There are two types of headaches that can occur after nitroglycerin administration:
- Immediate headaches: These occur within the first hour of application, are mild to moderate in severity, and ease spontaneously 2.
- Delayed headaches: These are moderate to severe, occur several hours after nitroglycerin administration, and can be migraine-type headaches 3, 2.
Mechanisms of Headache Development
The mechanisms behind these headaches are different:
- Immediate headaches are connected to vasodilation caused by nitric oxide (NO) release 2.
- Delayed headaches, or migraines, are triggered by other actions such as the release of calcitonin gene-related peptide or glutamate, or changes in ion channel function mediated by cyclic guanosine monophosphate or S-nitrosylation 2.
Alleviating Nitroglycerin-Induced Headaches
To alleviate these headaches, the following can be considered:
- Assessment of headache history: Before starting nitroglycerin treatment, it is essential to explore the patient's headache history to provide proper information and suitable treatment if needed 3.
- Dose adjustment: Since headaches are often dose-related, adjusting the dose of nitroglycerin may help alleviate headaches 4.
- Alternative treatments: For migraine-type headaches, anti-migraine medications such as triptans may be necessary. However, these are contraindicated in patients with certain medical conditions that are treated with nitrates, highlighting the need for new anti-migraine drugs that can be used in these patients 2.
Important Considerations
When using nitroglycerin, it is crucial to consider the following:
- Contraindications: Nitrates are contraindicated in patients with certain medical conditions, such as those taking phosphodiesterase-5 inhibitors, and in patients who experience syncope after nitrate administration 4.
- Side effects: Besides headaches, nitrates can cause other side effects, including hypotension, dizziness, and coronary steal 4.
Conclusion
Nitroglycerin-induced headaches can be a significant issue for patients. Understanding the types of headaches, their mechanisms, and how to alleviate them is essential for healthcare providers to manage these side effects effectively and improve patient outcomes.