Moxonidine

Indications

Moxonidine belongs to a group of drugs called anti-hypertensives that lower blood pressure. Moxonidine is used to treat high blood pressure.

Pharmacology

Stimulation of central alpha 2-adrenergic receptors is associated with sympathoadrenal suppression and subsequent reduction of blood pressure. As this class was further explored it was discovered that sympathoadrenal activity can also be suppressed by a second pathway with a newly discovered drug target specific to imidazolines. Specifically, moxonidine binds the imidazoline receptor subtype 1 (I1) and to a lesser extent αlpha-2-adrenoreceptors in the RSV causing a reduction of sympathetic activity, reducing systemic vascular resistance and thus arterial blood pressure

Moreover, since alpha-2-adrenergic receptors are considered the primary molecular target that facilitates the most common side effects of sedation and dry mouth that are elicited by most centrally acting antihypertensives, moxonidine differs from these other centrally acting antihypertensives by demonstrating only low affinity for central alpha-2-adrenoceptors compared to the aforementioned I1-imidazoline receptors.

Dosage And Administration

Adults (including the elderly): Your treatment will normally start with one 200 microgram tablet, taken in the morning. After three weeks, your doctor may increase this dose to 400 micrograms daily, given in a single dose in the morning, or in divided doses in the morning and evening. After another three weeks, your doctor may need to increase this dose to 600 micrograms daily, given in divided doses (morning and evening). You should not take more than 400 micrograms as a single dose, or more than 600 micrograms in any one day.

If you forget to take a dose, take one as soon as you remember, unless it is nearly time to take the next one. Do not take a double dose to make up for a forgotten dose.

If you forget to take a dose, take one as soon as you remember, unless it is nearly time to take the next one. Do not take a double dose to make up for a forgotten dose.

Interaction

Talk to your doctor if you are taking any of the following:

  • beta-blockers, such as propranolol or atenolol, used to treat heart problems
  • other medicines used to reduce blood pressure such as furosemide a diuretic, or captopril an angiotensin-converting enzyme inhibitor
  • antidepressants such as amitriptyline
  • sleeping tablets such as zopiclone, tranquilizers such as nitrazepam, lorazepam or phenobarbital
  • Moxonidine is removed from body by kidneys through the process called "tubular excretion". Other medicines removed from the kidneys in the same way could affect how moxonidine works.

Do not drink alcohol whilst taking Moxonidine.

Contraindications

Do NOT take Moxonidine if you:

  • Are allergic (hypersensitive) to moxonidine or any of the other ingredients of this medicine
  • Have a slow heart rate or suffer from an abnormal heart rhythm or a change in the rate of the heart beat (called “sick sinus syndrome” or “2nd or 3rd degree AV-block”
  • Have, or have had, heart failure or other heart problems

Side Effects

The following side effects have been reported at the approximate frequencies shown:

  • Very common: dry mouth, drowsiness
  • Common: headache, dizziness (vertigo), flushing (vasodilation), weakness or loss of strength, confusion, sleep disturbances, nausea (feeling sick), being sick (vomiting), stomach upsets (dyspepsia), diarrhoea, rash or itching (pruritus), back pain

Pregnancy And Lactation

Moxonidine is not recommended if you are pregnant, planning on becoming pregnant or are breastfeeding. Ask your doctor or pharmacist for advice before taking any medicine if you are pregnant or breastfeeding.

Precautions And Warnings

Tell your doctor before you start to take this medicine if you:

  • have a heart problem called "1st-degree AV-block"
  • have a severe coronary heart disease, or have angina (chest pain at rest)
  • have poor circulation
  • have kidney disease
  • have been told you have cerebrovascular insufficiency (poor blood supply to the brain which means you are at a greater risk of stroke)
  • are below 16 years of age
  • have a rare hereditary problem of galactose intolerance, Lapp lactase deficiency or glucosegalactose malabsorption as you should not take this medicine

Patients who are intolerant to lactose should note that Moxonidine tablets contain a small amount of lactose. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.

Overdose Effects

If you (or someone else) swallow a lot of the tablets all together, or if you think a child has swallowed any of the tablets, contact your nearest hospital casualty department or your doctor immediately. An overdose is likely to cause headache, sleepiness, dry mouth, loss of balance, dizziness, low blood pressure, slowing of the pulse, vomiting, feeling tired, weakness and pain in your stomach. Please take this leaflet, any remaining tablets and the container with you to the hospital or doctor so that they know which tablets were consumed.

Therapeutic Class

Anti-hypertensive

Use in special populations

Patients with kidney problems: If you have moderate problems with your kidneys, you should not take more than one 200 microgram tablet as a single dose or more than 400 micrograms in total, a day.

Children under 16 years of age: Moxonidine is not recommended for use in children.

Storage Conditions

Do not store above 30° C. Keep blister in the outer carton in order to protect from light.

Available Brand Names