Rilmenidine

BRAND NAMES

Rilmenidine, a prescription medication used to treat high blood pressure (hypertension), is available under several brand names internationally. 

Common brand names for Rilmenidine include:

• Albarel

• Cadrest

• Hyperdix

• Hyperium

• Iterium

• Tenaxum

MECHANISM OF ACTION

Rilmenidine is a centrally-acting antihypertensive agent that lowers blood pressure primarily through the selective stimulation of imidazoline I1 receptors in the brain's central nervous system (specifically the rostral ventrolateral medulla). It also has a minor affinity for central alpha-2 adrenoceptors. 

PHARMACOKINETICS:

Absorption

Rilmenidine is rapidly and extensively absorbed after oral administration, with an absolute bioavailability of close to 100%. 

Distribution

The distribution of rilmenidine encompasses both its dispersion within the body’s tissues and the geographic markets where it is commercially available.

Metabolism

Rilmenidine is minimally metabolized in the body and does not undergo significant presystemic (first-pass) metabolism in the liver.

Excretion

Rilmenidine is primarily excreted by the kidneys as the unchanged, or parent, drug. 

Key details regarding the excretion of rilmenidine:

• Major Route: Renal excretion is the main elimination process, accounting for approximately two-thirds (about 65%) of the total clearance.

PHARMACODYNAMICS

Rilmenidine’s pharmacodynamics involve its role as a centrally acting antihypertensive, mainly by selectively binding to imidazoline I-1 receptors in the brainstem, thereby decreasing sympathetic nervous system activity.

ADMINISTRATION

• Rilmenidine is administered orally, usually in tablet form.

• It is typically taken once daily, with or without food.

• The recommended starting dose is usually 1 mg per day for adults.

• Dose adjustments may be made based on blood pressure response and tolerability.

• It is important to take the medication at the same time each day for consistent blood pressure control.

DOSAGE AND STRENGTH

The dose of this medication varies by patient, so always follow your doctor’s instructions or the prescription label. It depends on the strength of the medicine, the number of doses per day, the interval between doses, and the condition being treated. For adults and teenagers 17 years and older, the usual dose for treating or preventing flu is 100 mg twice daily, while older adults typically take 100 mg once daily. Children’s doses are determined by age and weight, with specific guidelines for those 1–16 years, and use in children under 1 year must be decided by a doctor. Do not change your dose unless instructed by your healthcare provider.

DRUG INTERACTIONS

While some medications should never be taken together, others may be used concurrently even if an interaction is possible. In such cases, your doctor might adjust the dose or implement other safety measures. Always inform your healthcare provider about any prescription or over-the-counter (OTC) medications you are currently taking.

FOOD INTERACTIONS

Rilmenidine has a few specific and general food and substance interactions, primarily due to its blood pressure-lowering effects. 

Key Food & Substance Interactions

• Alcohol: Consumption is not recommended because it may enhance the sedative effects and further lower blood pressure.

• Garlic: Garlic interacts with rilmenidine and can further lower blood pressure.

• Ginger and Goldenseal: The interaction of ginger or goldenseal with rilmenidine may alter the effectiveness of the medication and produce changes in blood pressure. 

CONTRAINDICATIONS

Rilmenidine is contraindicated in individuals with a known hypersensitivity to any of its ingredients, in cases of severe depression, and in patients with severe renal insufficiency

SIDE EFFECTS

• Sleepiness or excessive drowsiness and general fatigue

• Dry mouth

• Lightheadedness or dizziness

• Headache

• Constipation

• Mood changes such as depression and anxiety

• Nausea and reduced appetite

• Sleep problems, including vivid dreams

• Sexual side effects, including impotence and decreased libido

OVER DOSE

An overdose of rilmenidine can lead to excessive lowering of blood pressure, resulting in symptoms such as severe dizziness, fainting, or slow heart rate. Other possible effects include drowsiness, fatigue, or confusion. In case of suspected overdose, seek immediate medical attention. Treatment is mainly supportive and may include monitoring vital signs, intravenous fluids, and medications to stabilize blood pressure and heart rate. Prompt medical intervention is essential to prevent serious complications.

TOXICITY

Rilmenidine is generally safe and well-tolerated when used at recommended doses for hypertension, with most side effects being mild and temporary. However, an overdose can lead to significant hypotension and reduced consciousness.