Version July 2025
Hypertension: Oral: Initial: 2.5 mg twice daily; may increase in increments of 2.5 mg/day at intervals ≥2 days until desired BP response is achieved; if divided doses are not the same, give the smaller dose in the morning and larger dose(s) in the afternoon; average dose: 25 mg/day (usually in 3 divided doses, but more frequent dosing may be required). Note: Avoid abrupt discontinuation; gradual tapering is recommended.
There are no dosage adjustments provided in the manufacturer's labeling; use with caution; use with extreme caution, if at all, if renal impairment is manifested by a rising or elevated BUN. Use is contraindicated in uremia.
There are no dosage adjustments provided in the manufacturer's labeling
Refer to adult dosing.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified. Frequency not defined.
Cardiovascular: Orthostatic hypotension, syncope
Central nervous system: Altered mental status, choreiform movements, convulsions, fatigue, orthostatic dizziness, paresthesia, sedation
Endocrine & metabolic: Decreased libido
Gastrointestinal: Anorexia, constipation (sometimes preceded by small, frequent stools), glossitis, intestinal obstruction, nausea, vomiting, xerostomia
Genitourinary: Impotence, urinary retention
Neuromuscular & skeletal: Tremor, weakness
Ophthalmic: Blurred vision, mydriasis
Respiratory: Pulmonary edema, pulmonary fibrosis
Hypersensitivity to mecamylamine or any component of the formulation; mild, moderate, labile hypertension (may not be suitable for uncooperative patients); coronary insufficiency or recent myocardial infarction; uremia; glaucoma; organic pyloric stenosis; coadministration with antibiotics or sulfonamides.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Concerns related to adverse effects:
• CNS effects: CNS effects, including tremor, choreiform movements, mental aberrations, and convulsions may occur (rarely), especially with large doses or in patients with cerebral or renal insufficiency. In addition, dizziness, lightheadedness, or fainting may also occur.
• Hypotension: When renal, cerebral, or coronary blood flow is deficient, any additional impairment, which might result from added hypotension, must be avoided. Therapeutic action may be potentiated by excessive heat, fever, infection, hemorrhage, pregnancy, anesthesia, surgery, vigorous exercise, other antihypertensive drugs, alcohol, or salt depletion.
• Paralytic ileus: Discontinue if signs of paralytic ileus occur (eg, frequent loose bowel movements with abdominal distention, decreased borborygmi)
Disease-related concerns:
• Cardiovascular disease: Use with caution in patients with marked cerebral and coronary arteriosclerosis or after a recent cerebral accident.
• Kidney impairment: Use with caution in patients with renal impairment. When renal impairment is manifested by a rising or elevated BUN, use with extreme caution, if at all. Since mecamylamine is excreted unchanged in the urine, renal impairment may reduce elimination and increase the risk of adverse effects including hypotension; the risk for neurological adverse effects is increased especially when large doses are administered to patients with renal impairment.
• Prostatic hyperplasia/urinary stricture: Use with caution in patients with prostatic hyperplasia, bladder obstruction, or urethral stricture; may cause urinary retention.
Other warnings/precautions:
• Abrupt discontinuation: Do not abruptly discontinue. Other antihypertensive therapy usually must be substituted.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Tablet, Oral, as hydrochloride:
Vecamyl: 2.5 mg
No
Tablets (Vecamyl Oral)
2.5 mg (per each): $75.84
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Oral: The morning dose should be relatively small and, in some instances, may even be omitted; the larger dose should be given at noon time and possibly in the evening. Administration after meals may cause a more gradual absorption and smoother control of excessively high BP; timing of relationship to meals should be consistent.
Hypertension: Management of moderately severe to severe hypertension and in uncomplicated malignant hypertension.
Sound-alike/look-alike issues:
Mecamylamine may be confused with mesalamine
None known.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Alcohol (Ethyl): May increase adverse/toxic effects of Mecamylamine. Risk C: Monitor
Alfuzosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Alkalinizing Agents: May increase serum concentration of Mecamylamine. Risk C: Monitor
Amifostine: Blood Pressure Lowering Agents may increase hypotensive effects of Amifostine. Management: When used at chemotherapy doses, hold blood pressure lowering medications for 24 hours before amifostine administration. If blood pressure lowering therapy cannot be held, do not administer amifostine. Use caution with radiotherapy doses of amifostine. Risk D: Consider Therapy Modification
Aminoglycosides: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Amphetamines: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Antipsychotic Agents (Second Generation [Atypical]): Blood Pressure Lowering Agents may increase hypotensive effects of Antipsychotic Agents (Second Generation [Atypical]). Risk C: Monitor
Arginine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Barbiturates: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Benperidol: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Brigatinib: May decrease antihypertensive effects of Antihypertensive Agents. Brigatinib may increase bradycardic effects of Antihypertensive Agents. Risk C: Monitor
Brimonidine (Topical): May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Bromperidol: May decrease hypotensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase hypotensive effects of Bromperidol. Risk X: Avoid
Capreomycin: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Colistimethate: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Dexmethylphenidate: May decrease therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Diazoxide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
DULoxetine: Blood Pressure Lowering Agents may increase hypotensive effects of DULoxetine. Risk C: Monitor
Flunarizine: May increase therapeutic effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Increasing Effects: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Herbal Products with Blood Pressure Lowering Effects: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Hypotension-Associated Agents: Blood Pressure Lowering Agents may increase hypotensive effects of Hypotension-Associated Agents. Risk C: Monitor
Iloperidone: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Indoramin: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Isocarboxazid: May increase antihypertensive effects of Antihypertensive Agents. Risk X: Avoid
Levodopa-Foslevodopa: Blood Pressure Lowering Agents may increase hypotensive effects of Levodopa-Foslevodopa. Risk C: Monitor
Lincosamide Antibiotics: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Loop Diuretics: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Lormetazepam: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Metergoline: May decrease antihypertensive effects of Blood Pressure Lowering Agents. Blood Pressure Lowering Agents may increase orthostatic hypotensive effects of Metergoline. Risk C: Monitor
Methylphenidate: May decrease antihypertensive effects of Antihypertensive Agents. Risk C: Monitor
Molsidomine: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Naftopidil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicergoline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nicorandil: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Nitroprusside: Blood Pressure Lowering Agents may increase hypotensive effects of Nitroprusside. Risk C: Monitor
Obinutuzumab: May increase hypotensive effects of Blood Pressure Lowering Agents. Management: Consider temporarily withholding blood pressure lowering medications beginning 12 hours prior to obinutuzumab infusion and continuing until 1 hour after the end of the infusion. Risk D: Consider Therapy Modification
Pentoxifylline: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Perazine: May increase hypotensive effects of Antihypertensive Agents. Risk C: Monitor
Pholcodine: Blood Pressure Lowering Agents may increase hypotensive effects of Pholcodine. Risk C: Monitor
Phosphodiesterase 5 Inhibitors: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Polymyxin B: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Prazosin: Antihypertensive Agents may increase hypotensive effects of Prazosin. Risk C: Monitor
Prostacyclin Analogues: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Quinagolide: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Silodosin: May increase hypotensive effects of Blood Pressure Lowering Agents. Risk C: Monitor
Sulfonamides: May increase adverse/toxic effects of Mecamylamine. Risk X: Avoid
Terazosin: Antihypertensive Agents may increase hypotensive effects of Terazosin. Risk C: Monitor
Tetracyclines: May increase neuromuscular-blocking effects of Mecamylamine. Risk X: Avoid
Thiazide and Thiazide-Like Diuretics: May increase adverse/toxic effects of Mecamylamine. Management: Consider avoiding the use of mecamylamine and thiazide diuretics. If combined, mecamylamine prescribing information suggests reducing the mecamylamine dose by 50% in order to avoid excessive hypotension. Risk D: Consider Therapy Modification
Urapidil: Antihypertensive Agents may increase hypotensive effects of Urapidil. Risk C: Monitor
Urinary Acidifying Agents: May decrease serum concentration of Mecamylamine. Risk C: Monitor
Vasopressin: Mecamylamine may increase therapeutic effects of Vasopressin. Specifically, the effect of vasopressin on mean arterial blood pressure may be increased. Risk C: Monitor
Mecamylamine crosses the placenta.
Due to the potential for serious adverse reactions in the nursing infant, the manufacturer recommends a decision be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of treatment to the mother.
Take after meals. Concomitant use of alcohol may potentiate the effects of mecamylamine.
Monitor BP (assess in the erect position before initiation and with dose increases), orthostatic vital signs, heart rate, and BUN.
Mecamylamine inhibits acetylcholine at the autonomic ganglia, causing a decrease in blood pressure. The blood pressure lowering effect is predominantly orthostatic; the supine blood pressure is also significantly decreased.
Onset: 0.5 to 2 hours
Duration: 6 to ≥12 hours
Absorption: Almost complete
Excretion: Urine (unchanged); rate of elimination is significantly affected by the pH of the urine. Acidic urine promotes excretion; alkalinization reduces excretion
