Mecamylamine is used to treat moderately severe to severe high blood pressure. It can also be used in sudden high blood pressure emergencies (malignant hypertension). Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems. Mecamylamine belongs to a class of drugs known as ganglion blockers. It works by relaxing blood vessels so blood can flow more easily.
Take this medication by mouth as directed by your doctor, usually 2 to 3 times daily. You may take this medication with or without food, but it is important to choose one way and take this medication the same way with every dose.
The dosage is based on your medical condition and response to treatment. To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose and gradually increase your dose. Follow your doctor's instructions carefully.
Take this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day. It is important to continue taking this medication even if you feel well. Most people with high blood pressure do not feel sick.
Do not stop taking this medication without consulting your doctor. A rapid rise in blood pressure may occur when this drug is suddenly stopped. This rapid rise in blood pressure may lead to stroke or heart failure that can be severe (possibly fatal). To prevent your blood pressure from getting too high if you are stopping treatment with this drug, your doctor may reduce your dose gradually and start you on another medication. Consult your doctor or pharmacist for more details. Report any new or worsening symptoms immediately.
It is important that you do not run out of mecamylamine or miss any doses. Tell your doctor or pharmacist right away if you are unable to take the medication (for example, due to vomiting).
When this medication is used for a long time, it may not work as well. Talk with your doctor if this medication stops working well. Tell your doctor if your condition does not improve or if it worsens (for example, your blood pressure readings remain high or increase).
Drowsiness, dizziness, lightheadedness, tiredness, blurred vision, decreased sexual ability/interest, nausea, constipation, and dry mouth may occur as your body adjusts to the medication. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Hot weather, exercise, or alcohol may increase dizziness and lightheadedness. Fever, vomiting, diarrhea, bleeding, loss of salt, or heavy sweating may also increase dizziness. To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.
To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
If you develop frequent diarrhea with severe stomach/abdominal discomfort and/or bloating while taking this medication, get medical help right away. This may be a sign of a very serious bowel disease (paralytic ileus).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking mecamylamine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: glaucoma, narrowing of the opening from stomach into intestines (organic pyloric stenosis), heart problems (such as chest pain, heart attack), blood flow problems especially to the brain (such as stroke), kidney disease, bladder/urination problems (such as bladder neck obstruction, urethral stricture), enlarged prostate (prostatic hypertrophy), salt-restricted diet.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is unknown if this medication passes into breast milk. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: ambenonium.
Other medications can affect the removal of mecamylamine from your body, which may affect how mecamylamine works. Examples include carbonic anhydrase inhibitors (such as acetazolamide), urinary alkalinizers (sodium/potassium citrate), sodium bicarbonate, among others.
Tell your doctor or pharmacist if you are taking other products that cause drowsiness, including alcohol, antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), muscle relaxants, and narcotic pain relievers (such as codeine).
Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness or increase your blood pressure. Ask your pharmacist about using those products safely.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe weakness, severe/sudden nausea and vomiting, anxiety, pounding heartbeat.
Do not share this medication with others.
Lifestyle changes that may help this medication work better include exercising, stopping smoking, and eating a low-cholesterol/low-fat diet. Consult your doctor for more details.
Laboratory and/or medical tests (such as blood pressure readings, kidney tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
Have your blood pressure checked regularly while taking this medication. Learn how to monitor your own blood pressure at home, and share the results with your doctor.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised November 2013. Copyright(c) 2013 First Databank, Inc.
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