Droxidopa 100 mg, 100 capsules: profile, composition and research

Reference page for Droxidopa 100 mg, 100 capsules. Active substance: Дроксидопа / Droxidopa.

Key facts

What droxidopa is

Droxidopa is a synthetic amino acid that the body converts into norepinephrine, the natural messenger that narrows blood vessels and raises blood pressure. Droxidopa itself is not a hormone: it is a prodrug from which enzymes gradually form the active substance.

It is supplied as 100 mg capsules, 100 capsules per pack. The active substance is droxidopa, and it is a prescription medicine.

Unlike norepinephrine, droxidopa can cross the blood-brain barrier. That matters because in neurological disease the signals to blood vessels are disrupted at the level of the nervous system itself.

How droxidopa works

Conversion into norepinephrine

The enzyme aromatic amino-acid decarboxylase removes a carboxyl group from droxidopa and turns it into norepinephrine. That acts on the vessels through adrenergic receptors, narrowing them and raising blood pressure.

Replacing a missing signal

In neurogenic orthostatic hypotension nerve endings release too little norepinephrine, and pressure falls sharply on standing. Droxidopa provides a source from which the missing messenger is formed.

Reaching the nervous system

Norepinephrine given directly does not cross the blood-brain barrier. Droxidopa gets across it and is converted into the active substance inside, which makes it suitable for acting on central pressure-regulating mechanisms.

Approved uses

The product information names neurogenic orthostatic hypotension — a sustained fall in blood pressure on standing — associated with Parkinson's disease, multiple system atrophy and primary autonomic failure.

Falling blood pressure during dialysis, familial amyloid polyneuropathy and other forms of autonomic failure are also noted. The diagnosis is confirmed by measuring blood pressure lying and standing.

Dose selection and how often the medicine is taken are decided by a physician, who takes age, symptoms and the risk of high pressure while lying down into account. This calls for regular medical supervision.

What the research shows

Droxidopa was studied in randomised placebo-controlled trials in patients with neurogenic orthostatic hypotension linked to Parkinson's disease and other neurodegenerative conditions. These trials assessed symptoms of dizziness on standing.

A meta-analysis pooled data from several studies and described the effect on symptoms and the safety profile. Separate work looked at whether treatment was associated with fewer falls.

The data do not support one identical outcome for every patient. Some studies were short, and results depended on the cause of the hypotension, so the decision is always individual.

Published research

Primary sources, verified against PubMed:

• Droxidopa for neurogenic orthostatic hypotension: a randomized, placebo-controlled, phase 3 trial., PubMed 24944260 (Neurology, 2014).
• Droxidopa in patients with neurogenic orthostatic hypotension associated with Parkinson's disease (NOH306A)., PubMed 24326693 (Journal of Parkinson's disease, 2014).
• Droxidopa for the short-term treatment of symptomatic neurogenic orthostatic hypotension in Parkinson's disease (nOH306B)., PubMed 25487613 (Movement disorders : official journal of the Movement Disorder Society, 2015).
• Droxidopa for the treatment of neurogenic orthostatic hypotension in neurodegenerative diseases., PubMed 30730771 (Expert opinion on pharmacotherapy, 2019).

Listed for reference. Publication of a study is not a claim about this particular product.

Precautions

• This is a prescription medicine. Prescribing and blood-pressure monitoring in different positions belong to a physician.
• The main risk is high blood pressure while lying down. Patients should measure their pressure and report headache or discomfort to the doctor.
• Nausea, dizziness, headache and other reactions are possible; any change in how you feel should be reported to the doctor.
• Do not take a double dose if you missed the previous one. This is stated in the manufacturer's information.
• Do not stop treatment on your own. Withdrawal and changes to the regimen are handled by a physician.
• Tell the doctor about pregnancy, breastfeeding and every medicine you take, including blood-pressure agents.

Frequently asked