Centrally acting imidazoline I1 agonist Pregnancy: No adequate data in pregnant women; animal studies have shown embryo-toxicological effects and the potential human risk is unknown. Should not be used during pregnancy unless clearly necessary. Secreted in breast milk — should not be used during breast-feeding; if therapy is considered absolutely necessary, breast-feeding must be stopped.

Moxonidine

Brand names: Physiotens

Moxonidine is a centrally acting antihypertensive used for mild to moderate essential hypertension, often when other agents are unsuitable or insufficient.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Adults: start with the lowest dose, 0.2 mg (200 micrograms) daily in the morning. If the therapeutic effect is insufficient the dose can be increased after three weeks to 0.4 mg (as a single morning dose or divided morning and evening); if still insufficient after a further three weeks it can be increased to a maximum of 0.6 mg divided morning and evening.

Route: Oral (may be taken before, during or after meals, with sufficient fluid)

Frequency: Once daily in the morning; 0.4 mg may be given once daily or in two divided doses, 0.6 mg must be given in two divided doses (morning and evening)

Max: A single dose of 0.4 mg and a daily dose of 0.6 mg should not be exceeded

Source: Moxonidine 200 microgram film-coated tablets SPC §4.2. Treatment should not be stopped abruptly but withdrawn over a period of two weeks; if moxonidine is used with a beta-blocker and both must be discontinued, stop the beta-blocker first and moxonidine a few days later. Elderly: provided renal function is not impaired, the dosage recommendation is the same as for adults; however the elderly may be more susceptible to cardiovascular effects, so start at the lowest dose and increase cautiously. Hepatic impairment: no studies available, but as moxonidine lacks extensive hepatic metabolism the dosage recommendation for mild to moderate hepatic impairment is the same as for adults. Paediatric population: moxonidine should not be given to children and adolescents under 16 years of age as insufficient therapeutic data are available.

Dose adjustments

Renal

Moderate renal impairment (GFR 30 to 60 ml/min): single dose not more than 0.2 mg and daily dose not more than 0.4 mg (SPC §4.2). SPC §4.4 adds: initiate at 0.2 mg daily; maximum 0.4 mg daily in moderate impairment and maximum 0.3 mg daily in severe renal impairment (GFR below 30 ml/min), if clinically indicated and well tolerated.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Sick sinus syndrome
Bradycardia (resting heart rate 50 beats/minute)
AV block 2nd and 3rd degree
Cardiac insufficiency

Side effects

Dry mouth (very common)
Headache, dizziness, somnolence, vertigo
Asthenia
Diarrhoea, nausea, vomiting, dyspepsia
Hypotension (including orthostatic); bradycardia; rash, pruritus

Interactions

Other antihypertensive medicinal products — additive blood-pressure-lowering effect (SPC §4.5)
Tricyclic antidepressants — may reduce the effectiveness of centrally acting antihypertensives; co-administration is not recommended, and moxonidine can potentiate their sedative effect (avoid co-prescribing) (SPC §4.5)
Tranquillisers, alcohol, sedatives and hypnotics — moxonidine can potentiate the sedative effect (SPC §4.5)
Lorazepam — moxonidine moderately augmented the impaired performance in cognitive functions (SPC §4.5)

Clinical monograph

How it works

It is a selective agonist at central imidazoline I1 receptors (with some alpha-2 adrenoceptor activity) in the brainstem, reducing sympathetic outflow and thereby lowering peripheral vascular resistance and blood pressure.

Prescribing in practice

Treatment should not be stopped abruptly because of the risk of rebound hypertension; withdraw gradually, and if a concomitant beta-blocker is also being stopped, stop the beta-blocker first.
It is contraindicated in significant bradyarrhythmias and certain conduction disorders, and caution is needed in renal impairment as it is largely renally excreted.
Common effects include dry mouth, headache, fatigue and dizziness; consult the SPC for full cautions.

Monitoring

Monitor blood pressure and heart rate, with attention to renal function in those with impaired kidneys.

Counselling the patient

Tell the patient not to stop the medicine suddenly and to seek advice before discontinuing.
Warn that dry mouth and drowsiness are common, especially early in treatment, and that alcohol may add to sedation.

Evidence & guidelines

Moxonidine is an established centrally acting antihypertensive; refer to current prescribing references for its place in therapy.

Reference: NICE NG136; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways