
Get clinician-approved Ketotifen for mast cell activation and neuroinflammation.
Only charged if approved
90-day supply + shipping
With RTHM discount
Paid every 90 days
(only charged if approved)
90-day supply + shipping, paid to the pharmacy
With RTHM discount
Ketotifen calms overactive histamine and chemical release in the body, often linked with conditions like MCAS, Long COVID, and ME/CFS.
By reducing chronic neuroinflammation and stabilizing your immune system, ketotifen can improve focus, memory, and overall cognitive function.
Ketotifen helps to accelerate recovery from symptom flares and PEM (post-exertional malaise) by reducing the inflammatory response.
Ketotifen is widely prescribed for the treatment of allergies, and can also be useful in managing symptoms triggered by mast cell activation syndrome (MCAS). MCAS symptoms can include:
Patients with Long COVID, ME/CFS, or other illnesses who experience these symptoms may find relief with ketotifen as well, because it helps to control the underlying mast cell activation that frequently contributes to these conditions.
Common side effects are typically mild and may include drowsiness, dry mouth, and increased appetite/weight gain. Many patients find that these effects diminish with continued use. It's advisable to have a healthcare provider determine the optimal starting dose and any potential interactions with other medications.
Ketotifen has been used safely for decades with a well-established safety profile.
Certain medical conditions can affect the use of this medication. Let your physician know if you have any of the following conditions:
You should not take ketotifen if you are on any of the following medications.
This 2023 study shows that many with Long COVID also experience a strong symptom overlap with mast cell activation syndrome (MCAS). H1 antihistamines and mast cell stabilizers (Ketotifen is both) are used to improve symptoms including skin, gastrointestinal, and neuropsychiatric symptoms in MCAS, and can be used to manage such symptoms in Long COVID.
"Immunological dysfunction and mast cell activation syndrome in long COVID"
View StudyThis 2023 study suggests that Ketotifen may help alleviate COVID-related brain fog by reducing chronic neuro-inflammation. Ketotifen achieves this by stabilizing mast cells—which directly activate microglia in the brain—and by inhibiting Kv1.3 potassium channels on brain leukocytes like microglia and lymphocytes. This dual action can suppress the overactive innate and adaptive immune responses responsible for neuropsychiatric symptoms such as short-term memory loss and difficulty concentrating in long COVID patients.
"Brain Leukocytes as the Potential Therapeutic Target for Post-COVID-19 Brain Fog"
View StudyRecent animal studies (2022 and 2023) have demonstrated ketotifen's effectiveness in reducing various types of inflammation. Specifically, research has shown that ketotifen suppresses neuroinflammation, reduces intestinal inflammation, and decreases systemic inflammation. These findings suggest potential therapeutic benefits for conditions characterized by chronic inflammatory processes.
"Repositioning of the anti-histaminic drug ketotifen fumarate as a neuro-modulatory and anti-inflammatory intervention in multiple sclerosis"
View StudyA 2023 patient registry analysis found that antihistamines like ketotifen were among the most frequently reported helpful interventions for Long COVID symptoms, particularly for cognitive dysfunction, fatigue, and post-exertional malaise.
"What helps Long Covid patients? Comparisons of complementary interventions for self-management"
View Study"After one month, I had no more gut issues. After two months, the burning went away in my fingers and toes. … and my mental state improved drastically. A dramatic difference."
"After about a month I noticed improvements. I’m 2 months now and I’d say my brain fog has lifted about 75-80%. I’m now doing things I haven’t done in 2 years. It’s a game changer."
"I took ketotifen during my long covid experience… I noticed improvements including better sleep, less congestion, less redness in the face and overall inflammation."