Cyclic vomiting syndrome (CVS) is a functional disorder defined by well-defined episodes of nausea, vomiting, and lethargy (tiredness). Note that nausea is listed first herein and not vomiting. Despite the name of the disease, nausea is usually the most troublesome symptom, and vomiting might be brief. Additional symptoms may or may not be present during episodes, especially including abdominal pain. When abdominal pain is the most troublesome symptom, patients may be labeled as having abdominal migraine. Other symptoms that can appear during episodes are headache, dizziness, and photophobia (light sensitivity), symptoms that overlap common forms of migraine. CVS, abdominal migraine, and migraine headache are generally thought to be a spectrum of related functional conditions.
Many different conditions have episodic nausea and vomiting. What distinguishes CVS from the other causes is that in CVS the episodes are:
- Multiple: They keep happening.
- Stereotypical: Episodes are all similar to each other.
- Distinct: Nausea and vomiting are much reduced or absent between episodes.
Some patients have nausea/vomiting episodes as their only disease manifestation. However, many (likely most) also suffer from other conditions (comorbidities), particularly other functional issues. Some of the common functional comorbidities to CVS include migraine headache, chronic fatigue, irritable bowel, gastroparesis, depression, anxiety, POTS and/or other forms of dysautonomia. Neuromuscular disease is present in about one-third of patients (“CVS+”), and can include intellectual disability, autism, seizures, and/or hypotonia.
In Dr. Boles’ experience, DNA sequence variants that likely serve as risk factors for disease can usually be identified in CVS patients. For more information on how genetic testing can be helpful in patients with CVS, please see pages 1-4 of the CVSA Code V newsletter by clicking this link. As this article demonstrates, identifying the underlying genetic factors leading to CVS can often be very helpful in directing therapy.
To see the abstracts (summaries) of Dr. Boles articles regarding CVS see https://www.ncbi.nlm.nih.gov/pubmed/?term=boles+rg+cyclic. Many of these studies demonstrate a degree of mitochondrial dysfunction in CVS. Based upon this work, it was shown that most patients with CVS have some degree of mitochondrial dysfunction. While some of these patients have mitochondrial disease as the cause of their CVS, in most of the cases CVS appears to be the result of many factors, of which one is mitochondrial related. This work is important because it suggests that mitochondrial-targeted therapies might be helpful in many (likely most) people with CVS. This is indeed the case in terms of Dr. Boles’ clinical experience, and the limited studies performed to date.
Mitochondrial-targeted therapies primarily include nutritional supplements. So, which, if any, supplements should a person with CVS take? Unfortunately, the answer is complicated, and depends on the patient’s age, severity of CVS, other disease manifestations, genetic factors, gut absorption, and tolerance of the GI tract to supplements. Thus, supplementation is best done under medical supervision.
The following information is intended to assist your physician in terms of starting dosages for commonly-used nutritional supplements in CVS.
Coenzyme Q10 (CoQ10)
- Promotes energy metabolism and an antioxidant.
- Common dose in adults and children over age 10 years: 300 mg twice daily (600 mg a day).
- Common dose in children under age 10 years: 10 mg/kg body weight twice daily.
- Side effects: Rare, occasional insomnia from being over-energized can be dealt with by moving forwards in time the last dose of the day.
- Caveats: Most brands have poor bioavailability. In Dr. Boles’ opinion, Trader Joes gel capsules are the best (Dr. Boles receives no money or goods from TJs).
- Blood testing: Level should be higher than 4.0 mg/L (4,000 mcg/L), which is much higher than the normal level. Blood should be drawn after 4+ hours from last meal or dose, and at least a week after any change in dosing.
L-carnitine
- Promotes the metabolism of fats and detoxification of metabolic intermediates from affected mitochondria.
- Common dose in adults and children over age 10 years: 500-1,000 mg twice daily (1,000-2,000 mg a day).
- Common dose in children under age 10 years: 50-100 mg/kg body weight twice daily.
- Side effects: Uncommon, occasional nausea or diarrhea (It is great for constipation); fishy odor. Side effects can be addressed by reducing the dose given.
- Caveats: Can be bought over-the-counter or by prescription. Choose the least-expensive option.
- Blood testing: Free level should be higher than 30-40 mcmol/L, which is the higher side of the normal level. Blood should be drawn after 4+ hours from last meal or dose, and at least a week after any change in dosing.
B vitamins
- There are several B vitamins that promote energy metabolism in different manners, including B1 (thiamine), B2 (riboflavin), B3 (niacinamide), B5 (pantothenate), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin). A B100 tablet contains all of these B vitamins, plus others, at very high mitochondrial-targeting dosages.
- Common dose in adults and children over age 10 years: One B100 tablet a day.
- Common dose in children under age 10 years: One half of a B100 tablet a day.
- Side effects: Nausea is common, so starting with one-half the dose for the first week is recommended. Some people can only tolerate one-half the dose.
- Caveats: There are many brands to choose from.
- Blood testing: Probably not helpful.
Vitamin C
- Promotes energy metabolism and an antioxidant.
- Common dose in adults and children over age 10 years: 500 mg twice daily (1,000 mg per day).
- Common dose in children under age 10 years: 250 mg twice daily (500 mg per day), less under age 5 years.
- Side effects: Very rare.
- Caveats: There are many brands to choose from. Vitamin C acts primarily as an antioxidant, whose main purpose is to prevent future deterioration. Thus, success may look like no changes.
- Blood testing: Probably not helpful.
Alpha lipoic acid (“ALA”)
- Antioxidant.
- Common dose in adults and children over age 10 years: 200 mg twice daily (400 mg per day).
- Common dose in children under age 10 years: 100 mg twice daily (200 mg per day), less under age 5 years.
- Side effects: Nausea occurs occasionally, so starting with one-half the dose for the first week is recommended. Some people can only tolerate one-half the dose.
- Caveats: There are many brands to choose from. ALA acts primarily as an antioxidant, whose main purpose is to prevent future deterioration. Thus, success may look like no changes.
- Blood testing: Probably not helpful.
Although some milder cases of CVS can be placed in remission by nutritional supplements alone, most patients with CVS also require medications. There are multiple medications that have been published in CVS, and/or are in use by CVS experts. Despite frequent side effects, amitriptyline is the most effective, and is considered to be the first drug to use in cases with CVS over the age of 5 years. Click on the following link for the article written by CVS experts, including Dr. Boles, in regard to CVS treatment recommendations in children: http://www.cvsaonline.org/pdfs/adams1-1.pdf.
The following publication, from 2011, covers the basics of Dr. Boles’ CVS management at that time: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3163531/pdf/1471-2377-11-102.pdf. This was before genetic testing in CVS, and his management has advanced considerably since then. However, this article can assist your physician in treating CVS with amitriptyline, coenzyme Q10 (“CoQ10”), and L-carnitine. Per the article, about 90% of CVS patients had significant improvement, a figure that has increased over time.
CVS is clearly a complicated disease to treat. In Dr. Boles’ experience, outcomes are much better in CVS in when an expert in involved in the care plan. A consultation with an expert is also cost effective, in reducing copays and other expenses related to hospitalizations and disability. If it is not practical to consult with Dr. Boles in California, he highly recommends that you contact the CVSA regarding finding another CVS expert.
