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Taking Antidepressants? Interactions to be Aware of.

posted Jul 2, 2013, 4:28 PM by Megan Black   [ updated Jul 8, 2013, 3:14 PM by Tascheleia Marangoni ]

    Each and every individual on the planet is unique and because of our differences we all have specific needs. Due to our differences, there isn’t a singular solution to treat depression. There are a variety of treatments for depression and one type of treatment includes antidepressants. Antidepressant medication prescribed by a professional health care provider has been shown to relieve some depressive symptoms.

    If you are taking antidepressants there are particular interactions with certain substances you should be aware of and they are alcohol, St. Johns Wort, caffeine and aspartame.

Alcohol Consumption:

    Alcohol is known to cause or worsen depression; therefore alcohol should be avoided while taking antidepressants. The consumption of alcohol while taking antidepressants is also not recommended by the manufacturers of antidepressant medication.

    The benefits of antidepressants are impaired even when only consuming a small amount of alcohol on a regular basis (e.g. one drink per day.) Generally speaking, most individuals can enjoy one to two drinks per week without experiencing any adverse effects while taking antidepressants. However, if you are going to have a drink while taking an antidepressant you should be cautious, as you may feel “heavily sedated,” “intoxicated”, or “you might even experience a hangover”.

St. Johns Wort:

    St. Johns Wort is a medicinal herb used to treat mild to moderate depressive symptoms with a high level of proven efficacy. It is possible that St. Johns Wort may interact with antidepressants used to treat depression or other mood disorders. If you are taking tricyclic antidepressants, selective serotonin reuptake inhibitors or monoamine oxidase inhibitors St. Johns Wort tends to increase the side effects and could cause a condition known as “serotonin syndrome.” For this reason, do not consume St. Johns Wort if taking antidepressants.
Mannel, M. (2004). Drug Interactions with St John's Wort. Drug Safety, 27(11), 773-797. (


    Caffeine is the mostly widely consumed central nervous system stimulant and it can be found in a variety of beverages ranging from soda, energy drinks, tea and coffee. Caffeine increases neuron firing in the brain, which ultimately results in a release of adrenaline by the adrenal glands. In addition, caffeine increases dopamine levels. Dopamine is a neurotransmitter that is found in the brain and is responsible for “mood, energy and metabolic functions.”
    For the most part, caffeine does not interact negatively with antidepressants. However, some antidepressants can raise blood pressure like caffeine does and should be avoided. If you experience feelings of “anxiousness or restlessness” while taking your antidepressant, caffeine can exacerbate such side effects. Lastly, some research suggests low doses of caffeine can actually improve the therapeutic outcome of antidepressants.

    Aspartame is the most abundantly stocked artificial sweetener on grocery store shelves today. The U.S Food and Drug Administration took over 20 years to approve aspartame and upon its approval, aspartame had never been tested on humans, only animals. The animal studies demonstrated that aspartame had carcinogenic effects and caused neurological issues.
    Approximately 50% of the aspartame molecule is phenylalanine, 40% is aspartic acid and 10% is methanol. Aspartic acid is a metabolite of aspartame that is an excitatory amino acid and is normally found in high levels in the brain. Methanol is “methyl alcohol or wood alcohol”. Methanol is found in antifreeze and is a toxicant that causes systemic toxicity. Lastly phenylalanine is an amino acid andhigh levels of phenylalanine can be found in blood. However, too much of the amino acid phenylalanine in the brain can cause brain damage and “decrease serotonin levels over time, leading to chemical imbalances that can cause mood disorders and depression.”

    A study conducted in 1993 by Walton et al. found that 30mg of aspartame a day for 7 days increased the severity of symptoms for patients with a history of depression. The study concluded, “individuals with mood disorders are particularly sensitive to this artificial sweetener and its use in this population should be discouraged.”