is a vasodilator medication primarily used to treat high blood pressure (hypertension) but has also been prescribed off-label for hair loss. Minoxidil for hair loss is prescribed at low doses to mitigate some of the risks.
SIDE EFFECTS
As with any medication, some users may experience side effects. The most common side effects of oral minoxidil include:
1. Unwanted hair growth: Some users may experience hair growth in areas other than the scalp, such as the face or other parts of the body.
2. Dizziness: Lightheadedness or dizziness may occur, especially when standing up from a sitting or lying position.
3. Fatigue: Some users may experience increased tiredness or weakness.
4. Headache: Some users may experience mild to moderate headaches.
5. Nausea or vomiting: Oral minoxidil may cause gastrointestinal upset in some users.
6. Fluid retention: This can lead to swelling (edema) in the extremities, such as the hands, feet, or ankles.
7. Heart palpitations: Some users may experience an increased heart rate or a sensation of a racing or pounding heartbeat.
8. Rapid weight gain: Sudden weight gain due to fluid retention may occur in some users.
9. Shortness of breath: Difficulty breathing, especially when lying down, may occur in some users.
10. Chest pain: Some users may experience chest pain or discomfort, although this is less common.
It's important to note that not everyone will experience these side effects, and some people may experience no side effects at all. If you are concerned about any potential side effects, it's best to speak with your healthcare provider before starting or continuing the medication.
WARNINGS
1. Salt and Water Retention: Minoxidil tablets must typically be used alongside a strong diuretic to prevent fluid retention and possible congestive heart failure. Monitoring body weight is essential. Without a diuretic, salt and water retention may occur, leading to edema. Diuretics, combined with salt restriction, usually minimize fluid retention. Refractory fluid retention might require discontinuation of minoxidil or temporary cessation followed by resuming treatment with aggressive diuretic therapy.
2. Preventing Tachycardia: Minoxidil increases heart rate and may worsen or induce angina due to increased oxygen demands. This can be prevented by administering a beta-adrenergic blocker or other sympathetic nervous system suppressant. Continuous effectiveness of the suppressant should be ensured.
3. Pericarditis, Pericardial Effusion, and Tamponade: Minoxidil has been associated with pericarditis, pericardial effusion, and tamponade in about 3% of treated patients, especially those with impaired renal function. Patients should be closely monitored for pericardial disorders, and appropriate interventions should be applied if necessary. If effusion persists, consider discontinuing minoxidil.
4. Interaction with Guanethidine: Minoxidil may cause profound orthostatic effects in patients receiving guanethidine. If possible, guanethidine should be stopped before starting minoxidil. If not, initiate minoxidil therapy in a hospital setting.
5. Rapid Control of Blood Pressure Risks: In patients with severe hypertension, rapid blood pressure control can cause syncope, cerebrovascular accidents, myocardial infarction, and sensory organ ischemia. Minoxidil initiation in malignant hypertension patients should occur in a hospital setting to monitor blood pressure changes.
6. In animal studies, minoxidil was found to induce various types of myocardial lesions and other negative cardiac consequences (see CARDIAC LESIONS IN ANIMALS).
If you are experiencing a medical emergency, please call 911 or seek immediate medical attention.
You are encouraged to report negative side effects of prescription products to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.
This information is not comprehensive. Please visit dailymed.nlm.nih.gov for more information.