Mecamylamine

Mecamylamine is a prescription medication used for the treatment of hypertension (high blood pressure). 

• Mecamylamine is available under the following different brand names: Inversine, Vecamyl

Common side effects of Mecamylamine include:

• Dizziness,
• Fainting,
• Nausea,
• Vomiting,
• Loss of appetite,
• Constipation,
• Dry mouth,
• Swollen tongue,
• Weakness,
• Tiredness,
• Blurred vision,
• Impotence, and
• Decreased interest in sex.

Serious side effects of Mecamylamine include:

• Hives,
• Difficulty breathing,
• Swelling of the face, lips, tongue, or throat,
• Tremors,
• Jerky muscle movements,
• Numbness,
• Tingling,
• Burning pain,
• Painful or difficult urination,
• Ongoing diarrhea with stomach bloating,
• Confusion,
• Thinking problems,
• Lightheadedness,
• Seizure,
• Dry cough,
• Wheezing, and
• Shortness of breath

Rare side effects of Mecamylamine include:

• None 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult dosage

Tablet

• 2.5 mg

Hypertension

Adult dosage

• 2.5 mg orally two times a day initially; may increase by 2.5 mg increments at intervals not less than 2 days.
• The average total daily dose is 25 mg (in 3 divided doses); however, as little as 2.5 mg/day may be sufficient.

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Mecamylamine has severe interactions with no other drugs.
• Mecamylamine has serious interactions with the following drug:
  • lofexidine
• Mecamylamine has moderate interactions with the following drug:
  • xipamide
• Mecamylamine has minor interactions with the following drugs:
  • agrimony
  • bethanechol
  • brimonidine
  • cornsilk
  • forskolin
  • maitake
  • niacin
  • octacosanol
  • reishi
  • shepherd's purse
  • tizanidine
  • treprostinil
  • vasopressin

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, health questions, or concerns.

Contraindications

• Hypersensitivity to mecamylamine
• Coronary insufficiency, glaucoma, recent MI, pyloric stenosis, renal insufficiency, uremia
• Do not use w/antibiotics, sulfonamides.

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Mecamylamine?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Mecamylamine?”

Cautions

• Arteriosclerosis, bladder neck obstruction, urethral stricture, cerebral insufficiency, gastrointestinal obstruction, prostatic hypertrophy
• Potentiation of hypotensive effects due to excessive heat, fever, infection, hemorrhage, pregnancy, anesthesia, alcohol consumption, salt depletion, or diarrhea
• Avoid abrupt withdrawal.
• Rarely used.

Pregnancy and Lactation

• Use with caution if benefits outweigh risks during pregnancy.
• Lactation
  • May cross into the breast milk, use caution.