Cognitive Behavioral Therapy for ADHD adults

Step away from the orange juice, and no one gets hurt.
It’s well understood that drug interactions exist for just about every medication, but the specifics of ADHD medication interactions are widely unknown. There are plenty of warnings about the overuse of such medications, but there’s not enough talk about the variables that can lower the effectiveness of drugs like Adderall, Ritalin, and Vyvanse.
While there are many reasons why your medication may not work in the way you expect, one of the most common explanations for ineffective ADHD medications is Vitamin C, or ascorbic acid. If you've heard of "The Grapefruit Rule", this is the scientific explanation you've been looking for.
Vitamin C, also known as ascorbic acid, is an important nutrient and antioxidant your body uses to synthesize connective tissues and strengthen your immune system, among other functions.[1] Vitamin C is not made or stored by your body, which is why it’s important to consistently include it in your diet.
Vitamin C is mostly found in foods containing citrus (citric acid)[2], but other foods have this vitamin as well.
Common sources of vitamin C include:
While it’s crucial to include vitamin C in your diet each day, it’s also important to be aware of when you consume foods containing this nutrient because ascorbic acid is known to negatively interact[3] with amphetamines - a drug commonly used to treat ADHD.
To date, the only ADHD medications known to interact with vitamin C are those containing amphetamine and/or dextroamphetamine. This is due to the high alkalinity of amphetamine-based medications, as well as their tendency to be attracted to ascorbic acid.[4]
These medications include:
*The initial drug form (pro-drug) in Vyvanse is lisdexamfetamine; however, it's metabolized by the liver and "turned into" dextroamphetamine.
Think back to your high school chemistry class, and you may recall lessons on acids and bases. Acids are on the lower end of the pH scale, while bases (alkalines) are on the higher end. In the middle of the scale is the number “7”, which indicates neutrality – neither basic nor acidic.
To simplify, strong acids neutralize strong bases, and vice versa.
Now let’s think back to biology classes — recall anything about the digestive system? If not, here’s a quick review:
When we consume things (food, medicine, etc.) they're transported to the stomach to await complete digestion. Part of this digestion process involves the absorption of nutrients and/or chemicals into the bloodstream, which occurs through the walls of your digestive tract.
Once absorbed, nutrients and chemicals hitch a ride via the cardiovascular system (AKA your bloodstream), where they’re eventually transported to their destination.
Put simply, stimulant medications target your Central Nervous System, or CNS.[5] Each of the different types of stimulants may have their own mechanisms, but their final destination is the same - the brain. However, because the medications are first absorbed into the bloodstream, they don’t act on the CNS right away. (This is why it can take up to two hours for some people to feel the effects of stimulant medication.)
And before absorption, amphetamines travel along the digestive tract along with whatever else you may have in your system at the time, which leaves time for interactions.
Enter: vitamin C, a strong acid with the ability to attract bases — and neutralize them.
If the amphetamines come into contact with ascorbic acid molecules before they reach the adrenal glands or liver (or other bodily structures or organs involved with drug metabolism and the Central Nervous System), they will be unable to reach the brain and work effectively.
What’s left of the amphetamine may be able to have some effect on the brain, but most of it is transported to the kidneys and flushed out during your next bathroom visit.[6]
As mentioned, vitamin C is a vital nutrient for your health, so it’s extremely unsafe to avoid it just for the sake of improving the effectiveness of your medication.[7] But there are ways to take your medicine and still get the recommended amount of vitamin C.
Here are a few tips:
Other ADHD medications (i.e. those that do not contain amphetamines) are not likely to be affected by ascorbic acid in the same way that Adderall is. However – like with all information presented here – it’s always a good idea to check with your doctor before making any decisions about your diet or treatment regimen.
Methylphenidate medications are also stimulants, but they are more acidic than amphetamines, making them less susceptible to the hindrance effect of vitamin C.
Common methylphenidate medications used to treat ADHD include:
Because non-stimulant medications use an entirely different mechanism to treat ADHD, their efficacy is unlikely to be immediately affected by vitamin C.
Common non-stimulants that are used to treat ADHD include[8] (but are not limited to):
Adderall and Vyvanse are amphetamine-based stimulant medications that are used to treat ADHD. Because amphetamine is a strong alkaline (base), it is susceptible to being hindered “ineffective” by vitamin C (ascorbic acid), which acts as a magnet for amphetamines.
Moral of the story: don’t ingest vitamin C within an hour (before and after) of taking your stimulant medication.
I also made a video on the science of ADHD medication back when I was striving to be a YouTuber - for anyone that prefers watching videos to reading articles.
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