{"id":72,"date":"2022-11-15T17:09:17","date_gmt":"2022-11-15T17:09:17","guid":{"rendered":"https:\/\/oxfordhealth.nhs.uk\/ips\/?page_id=72"},"modified":"2026-03-10T09:47:07","modified_gmt":"2026-03-10T09:47:07","slug":"risks-benefits","status":"publish","type":"page","link":"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/","title":{"rendered":"Risks and benefits"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\"><p class=\"ez-toc-title\" style=\"cursor:inherit\">Sections<\/p>\n<\/div><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Potential_side_effects\" >Potential side effects<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Dependence\" >Dependence<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Tolerance\" >Tolerance<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Bladder_damage\" >Bladder damage<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Cognitive_impairment\" >Cognitive impairment<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Personality_change\" >Personality change<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Benefits\" >Benefits<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/oxfordhealth.nhs.uk\/ips\/ketamine-trd\/risks-benefits\/#Non-urgent_advice_Downloadable_information\" >Non-urgent advice: Downloadable information<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Potential_side_effects\"><\/span>Potential side effects<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Ketamine is not a licensed treatment for depression and the effects of taking it long term are unknown. There may also be unusual side-effects which occur acutely which have not yet been reported.<\/p>\n<p>About 10% of people who have a ketamine infusion have an experience that is very challenging.\u00a0 If you find any of the side effects too unpleasant then these will almost always resolve within 15 minutes of stopping the infusion. Occasionally people experience a worsening in their depressive symptoms and suicidality which persists for up to two weeks after taking ketamine.\u00a0 Sometimes this is sufficiently unpleasant that they do not want to take further ketamine.\u00a0 Those who do persist with further treatment often find that it starts to help after 1-2 more infusions.<\/p>\n<p>Of the remaining 90%, about half have a very pleasant experience and in the remainder it is neither unpleasant nor pleasant.<\/p>\n<details class=\"nhsuk-details nhsuk-expander\">\n                    <summary class=\"nhsuk-details__summary\">\n                        <span class=\"nhsuk-details__summary-text\">Brief side effects<\/span>\n                    <\/summary>\n                    <div class=\"nhsuk-details__text\">\n<p>Ketamine commonly causes brief side effects. These are more common at higher doses, but the relationship between dose and side-effects is variable, even within the same patient.<\/p>\n<p>Side-effects which occur during or shortly after treatment include:<\/p>\n<p><strong>Feeling dissociated (mind and body feel separate).<\/strong> Occasionally, this extends to the point of an \u2018out of body\u2019 experience. \u2018My feet didn\u2019t seem as if they belonged to me\u2019. A floating sensation.<\/p>\n<p><strong>\u2018Ego dissolution\u2019.\u00a0<\/strong> The feeling of \u2018oneness with everything\u2019, as if you are a drop of water being dropped into a river. A feeling of being very tiny, like an electron or atom. Often accompanied by a sense of awe \u2013 but can be experienced as frightening.<\/p>\n<p><strong>Dizziness.<\/strong><\/p>\n<p><strong>Feeling a bit drunk or lightheaded.<\/strong><\/p>\n<p><strong>Feeling tired for the rest of the day after treatment.<\/strong><\/p>\n<p><strong>Altered perception.<\/strong> Things \u201clook peculiar\u201d or sound different.<\/p>\n<p><strong>Nausea or vomiting.<\/strong> This can be treated with antinausea agents.\u00a0 If you feel sick, we will give you ondansetron with your next and subsequent infusions. Do not have a big meal before treatment.<\/p>\n<p><strong>Anxiety.<\/strong> This can extend to the point of panic. It may be associated with a \u2018near death\u2019 experience. This can occur \u2018out of blue\u2019 even in people who have had many treatments. The anxiety diminishes rapidly as the drug is broken down in the body, so the infusion can be turned off if necessary. In this case, the anxiety settles within 5-10 minutes.<\/p>\n<p><strong>Headache.<\/strong> Usually responds to paracetamol.<\/p>\n<p><strong>Tinnitus \u2013 a ringing in the ears.\u00a0<\/strong> This can get louder in those who already experience it, or start in people who have never had it.\u00a0 It is probably more likely if you are also taking drugs with tinnitus listed as a known side-effect such as venlafaxine and duloxetine. The tinnitus usually resolves if the ketamine is stopped.\u00a0 If the ketamine is not stopped, it is possible that hearing may be affected so it is important you let us know if you develop tinnitus.<\/p>\n<p><strong>Temporary bruising.<\/strong> The treatment involves a needle being put into the vein on the back of your hand and a low dose of ketamine infused over 40 minutes.<\/p>\n<p><strong>An increase in blood pressure or a fast heart rate.<\/strong> The extent of this comparable to changes that occur naturally in everyday activities.\u00a0 Therefore, we do not monitor this routinely after the first infusion.\u00a0 If you would like us to do so, please say.<\/p>\n<\/div>\n                <\/details>\n<details class=\"nhsuk-details nhsuk-expander\">\n                    <summary class=\"nhsuk-details__summary\">\n                        <span class=\"nhsuk-details__summary-text\">Less-common side effects<\/span>\n                    <\/summary>\n                    <div class=\"nhsuk-details__text\">\n<p><strong>Vivid dreams.<\/strong><\/p>\n<p><strong>Hallucinations.<\/strong> Feeling, seeing or hearing something that is not actually there.<\/p>\n<p><strong>Mania.<\/strong> Unusually elevated mood which causes problems. Ketamine should be stopped immediately if you suspect this is happening. The ketamine team and your local team need to be informed promptly.<\/p>\n<\/div>\n                <\/details>\n<details class=\"nhsuk-details nhsuk-expander\">\n                    <summary class=\"nhsuk-details__summary\">\n                        <span class=\"nhsuk-details__summary-text\">Rare physical side-effects<\/span>\n                    <\/summary>\n                    <div class=\"nhsuk-details__text\">\n<p><strong>Liver damage.<\/strong> Rarely, people taking very regular ketamine experience liver damage.\u00a0 This is sufficiently rare that we do not routinely check this.\u00a0 However, if you feel unwell during ongoing ketamine treatment, please let us know and we will review whether you need a blood test.<\/p>\n<\/div>\n                <\/details>\n<details class=\"nhsuk-details nhsuk-expander\">\n                    <summary class=\"nhsuk-details__summary\">\n                        <span class=\"nhsuk-details__summary-text\">Long term theoretical risks<\/span>\n                    <\/summary>\n                    <div class=\"nhsuk-details__text\">\n<h3><span class=\"ez-toc-section\" id=\"Dependence\"><\/span>Dependence<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sometimes people find that if they stop ketamine their depression relapses. This is not the same as addiction. This is reliance.<\/p>\n<p>However, non-clinical ketamine is sometimes taken illegally in large, frequent doses and cause addiction.\u00a0 This has not happened in any of the patients treated with our protocol.\u00a0 For further discussion of addiction see our <a href=\"https:\/\/oxfordhealth.nhs.uk\/ketamine\/faq\/\">FAQs<\/a><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tolerance\"><\/span>Tolerance<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>It is not uncommon for patients taking ketamine for depression to find that their depression, which was initially relieved by the ketamine, is no longer controlled despite continuing to have treatment with ketamine. There can be several possible reasons, one of which is that they have developed tolerance to ketamine. This may mean that a treatment break is needed or that it is no longer an effective treatment and therefore will be stopped. Sometimes, the dose can be safely increased. Keeping the interval between doses as long as possible helps to maintain the effect.\u00a0 Adding a regular weekly dose of oral ketamine, taken at home, between monthly infusions, is another common way of managing this.\u00a0 We can also use other medicines successfully to augment the effect of the ketamine.<\/p>\n<p>Rarely, people find that they think a lot about ketamine and crave it. It is important to notice that this is happening and to be open and honest with the clinical team about this.<\/p>\n<p>For comparison, ketamine is much less addictive and dangerous than strong opiates (eg fentanyl, methadone) or nicotine, probably less addictive than benzodiazepines and probably about as addictive as whiskey.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Bladder_damage\"><\/span>Bladder damage<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Bladder damage. This is common in people who take illegal ketamine recreationally, usually at nasal doses of over 1g ketamine daily. This dose is much higher than the maximum we use.<\/p>\n<p>The main symptoms of ketamine-induced bladder damage are lower abdominal pain, pain passing urine, and needing to pass urine more often. If you start to experience these symptoms please contact your GP and the ketamine clinic.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Cognitive_impairment\"><\/span>Cognitive impairment<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>This has not been observed over 1 year treatment with esketamine, or in our patients, but has been seen in addicts taken high doses daily. It is associated with evidence of brain shrinking and other brain lesions.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Personality_change\"><\/span>Personality change<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Apathy has been reported in addicts but not in patients receiving medical doses.<\/p>\n<\/div>\n                <\/details>\n<h2><span class=\"ez-toc-section\" id=\"Benefits\"><\/span>Benefits<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Ketamine is a treatment for depression which has not responded to other treatments. A rapid antidepressant effect has been demonstrated in many clinical trials of single intravenous infusions over the last 20 years in patients with depression which has not responded to at least 2 or 3 antidepressants.<\/p>\n<p>The response lasts at least a day for about 70% of patients and up to three days for 30% of patients. The majority of patients relapse within two weeks after treatment.<\/p>\n<p>In our clinic 50% of people who try ketamine have enough of a benefit that they think it is worth continuing with it.<\/p>\n<p>It is important to recognise that ketamine is not licensed as an antidepressant. It has not been evaluated in large, or long term, clinical trials. \u00a0This means that the long-term success rates have not been fully documented.<\/p>\n<p>Large trials of the closely related drug esketamine, which is a component of ketamine, have shown broadly similar effects. A safety study of over 800 patients who took intranasal esketamine and a newly initiated antidepressant showed a 43% remission rate after 12 months of treatment. Remission is when there are no longer any significant symptoms of depression.\u00a0 For comparison, a large randomised study of people with depression found that those whose depression had not responded adequately to two previous antidepressants had a 5% chance of being in remission 12 months later if they tried a third antidepressant.<\/p>\n<div class=\"nhsuk-care-card nhsuk-care-card--non-urgent\">\n                <div class=\"nhsuk-care-card__heading-container\">\n                    <h3 class=\"nhsuk-care-card__heading\"><span class=\"ez-toc-section\" id=\"Non-urgent_advice_Downloadable_information\"><\/span><span role=\"text\"><span class=\"nhsuk-u-visually-hidden\">Non-urgent advice: <\/span>Downloadable information<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n                    <span class=\"nhsuk-care-card__arrow\" aria-hidden=\"true\"><\/span>\n                <\/div>\n                <div class=\"nhsuk-care-card__content\">\n<div class=\"nhsuk-action-link\"><a class=\"nhsuk-action-link__link\" href=\"https:\/\/oxfordhealth.nhs.uk\/wp-content\/uploads\/sites\/36\/2024\/03\/Full-information-about-Oxford-ketamine-service-v2.1-190224.pdf\" target=\"_self\"><span class=\"nhsuk-action-link__text\">Full information about Oxford ketamine service v2.1 19 Feb 2024 (PDF)<\/span><\/a><\/div>\n<p>This PDF contains all the text on the website, used for consent.<\/p>\n<\/div>\n            <\/div>\n","protected":false},"excerpt":{"rendered":"<p>Potential side effects Ketamine is not a licensed treatment for depression and the effects of taking it long term are&#8230;<\/p>\n","protected":false},"author":1,"featured_media":573,"parent":8,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"template-page-vertical-nav.php","meta":{"_acf_changed":false,"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","footnotes":""},"class_list":["post-72","page","type-page","status-publish","has-post-thumbnail","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/pages\/72","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/comments?post=72"}],"version-history":[{"count":4,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/pages\/72\/revisions"}],"predecessor-version":[{"id":438,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/pages\/72\/revisions\/438"}],"up":[{"embeddable":true,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/pages\/8"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/media\/573"}],"wp:attachment":[{"href":"https:\/\/oxfordhealth.nhs.uk\/ips\/wp-json\/wp\/v2\/media?parent=72"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}