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Study on Ketamine and Magnesium Sulfate for Treating Chronic Cluster Headache in Patients Unresponsive to Standard Treatments

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a severe type of headache known as chronic cluster headache, which is a condition that causes intense pain and is difficult to treat with standard medications. The study is exploring the use of two well-known medications, ketamine and magnesium sulfate, to see if they can help relieve this type of headache in patients who have not found relief with other treatments. The trial will compare the effects of a single infusion of these medications to a control group receiving hydroxyzine, which acts as an active placebo.

The purpose of the study is to evaluate the effectiveness of this treatment approach. Participants will receive the treatment through an intravenous infusion, which means the medication is delivered directly into the bloodstream. The study will monitor changes in the frequency and intensity of headache attacks over several weeks following the infusion. Participants will also be assessed for any side effects and their overall response to the treatment.

Throughout the study, researchers will collect data on how often and how severe the headaches are, as well as any changes in anxiety and depression levels. The study aims to provide insights into whether this combination of medications can offer a new option for those suffering from chronic cluster headaches who have not benefited from existing treatments.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit

    Upon joining the study, the first step involves an initial visit to the clinical trial site. During this visit, eligibility is confirmed based on specific criteria, such as age and diagnosis of chronic cluster headache.

    A detailed explanation of the trial process is provided, and informed consent is obtained. This ensures understanding and agreement to participate in the study.

  2. Step 2

    Pre-treatment assessment

    Before receiving any treatment, a pre-treatment assessment is conducted. This includes recording the frequency of headache crises over a 14-day period.

    This assessment helps establish a baseline for comparing the effects of the treatment.

  3. Step 3

    Treatment administration

    The treatment involves a single intravenous infusion of ketamine combined with magnesium sulfate. This is administered at the clinical trial site.

    Some participants may receive hydroxyzine as an active placebo, which is a substance with no therapeutic effect used for comparison.

  4. Step 4

    Post-treatment monitoring

    After the infusion, monitoring occurs to observe any changes in the frequency and intensity of headache crises.

    This monitoring period includes several checkpoints: days 7-13, 14-20, 21-27, and 28-34 post-infusion.

  5. Step 5

    Follow-up assessments

    Follow-up assessments are conducted to evaluate the overall response to the treatment. This includes measuring the frequency of headache crises and any changes in anxiety and depression levels.

    Additional assessments may include evaluating the need for further treatment and any side effects experienced.

  6. Step 6

    Final evaluation

    A final evaluation is conducted on day 90 to assess the long-term effects of the treatment.

    This evaluation includes a comprehensive review of the patient's condition and any changes in their headache patterns.

Who can join the trial?

5 criteria

  • Must be 18 years or older.
  • Must have a diagnosis of chronic cluster headache according to specific medical guidelines (ICHD-3 criteria).
  • Must experience at least 2 headache attacks per day on average during the 14 days before receiving the study treatment.
  • Must have tried and found three major treatments for cluster headaches (verapamil, lithium, and corticosteroids) to be ineffective, not tolerated, or unsuitable for use.
  • Must provide informed consent, meaning you agree to participate after understanding the study details.

Who cannot join the trial?

3 criteria

  • Patients who do not have refractory chronic cluster headache cannot participate. This means the study is only for those who have a specific type of headache that does not respond to usual treatments.
  • Patients who are not within the specified age range cannot participate. The study is for adults aged 18 to 65 years old.
  • Patients who are part of a vulnerable population cannot participate. This includes groups who may need special protection or care.
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Investigated drugs

  • Ketamine

    is a medication that is often used for pain relief and as an anesthetic. In this trial, it is being tested to see if it can help reduce the pain from chronic cluster headaches, which are severe headaches that occur in cycles. Ketamine works by affecting certain chemicals in the brain to help decrease pain and discomfort.

  • Magnesium sulfate

    is a mineral that is sometimes used to treat low levels of magnesium in the blood. In this trial, it is being used alongside ketamine to see if it can enhance the pain-relieving effects for people suffering from chronic cluster headaches. Magnesium sulfate may help by relaxing blood vessels and reducing inflammation, which can contribute to headache relief.

  • Hydroxyzine

    is a medication that is commonly used to treat anxiety and tension. In this trial, it is used as a comparison treatment to see how effective the combination of ketamine and magnesium sulfate is. Hydroxyzine can help calm the nervous system, which might provide some relief from headache symptoms, but it is not the main focus of the study.

What is already known about the treatment

  • Ketamine

    Ketamine is administered as an infusion, meaning it is given directly into the bloodstream through a vein. It is currently being studied for its effectiveness in treating chronic refractory cluster headaches, which are severe headaches that do not respond to typical treatments. Ketamine works by blocking certain receptors in the brain, which can help reduce pain. It is classified as an anesthetic, but in this context, it is used for its pain-relieving properties.

  • Magnesium sulfate

    Magnesium sulfate is also given as an infusion, delivered directly into the bloodstream. It is being evaluated in combination with ketamine for its potential to help treat chronic refractory cluster headaches. Magnesium sulfate may help by relaxing blood vessels and reducing inflammation, which can contribute to headache relief. It is classified as a mineral supplement and is often used to treat magnesium deficiencies and other conditions.

  • Hydroxyzine

    Hydroxyzine is administered orally or as an injection and is used in this trial as an active placebo, meaning it is given to the control group to compare the effects of the main treatment. It is not intended to treat cluster headaches in this study but is used to help understand the effectiveness of the ketamine and magnesium sulfate combination. Hydroxyzine works by blocking certain natural substances in the body that cause allergic reactions and is classified as an antihistamine.

Investigated diseases

Refractory Chronic Cluster Headache – Refractory chronic cluster headache is a neurological disorder characterized by severe, recurring headaches that are resistant to standard treatments. These headaches typically occur in cyclical patterns or clusters, with each episode lasting from weeks to months, followed by periods of remission. The pain is usually unilateral, centered around one eye, and can be accompanied by symptoms such as tearing, nasal congestion, or drooping eyelids. The exact cause of cluster headaches is not well understood, but they are believed to involve abnormalities in the hypothalamus and disruptions in circadian rhythms. The condition is more common in men and often begins in adulthood. Over time, the frequency and intensity of the headache episodes can vary, making management challenging.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-518943-38-00Protocol codeRBHP 2020 MOISSETEstimated enrolment90 patientsSponsorUniversity Hospital Of Clermont-Ferrand

sourced from the EU Clinical Trials Register and site verification

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