A study comparing the reduction in caffeine withdrawal symptoms in heavy coffee drinkers found that giving these individuals decaffeinated coffee can substantially reduce caffeine withdrawal symptoms, even when they are told that it is decaffeinated. The study was published in the Journal of Psychopharmacology.
When a person addicted to a certain drug suddenly stops using that drug, he/she typically experiences a set of extremely unpleasant symptoms. Symptoms can depend on the type of drug, but they generally involve irritability, changing moods, aches and pains, craving for the drug, depression, anxiety, not being able to sleep and others. The sheer magnitude and unpleasantness of these symptoms is one of the main barriers that prevent people from quitting drugs of dependence.
Due to this, finding ways to reduce or prevent the onset of withdrawal symptoms has been one of the main strategies in treating addictions. But even the best existing treatments have limited effectiveness and a significant share of patients eventually returns to using drugs even after managing to abstain from their use for some time.
Researchers are constantly looking for novel ways to treat addictions and reduce withdrawal symptoms. One of the novel approaches attracting quite a bit of research interest is to use the placebo effect. The placebo effect is a beneficial effect that is produced by a drug or a treatment that has no way of producing such an effect and which is due to the patient believing in that treatment.
Studies so far have shown that the placebo effect can be detected in a wide range of psychophysiological phenomena such as reducing pain, improving sleep or motor function, widening breathing pathways in some medical conditions related to the respiratory system and others.
Study author Llewellyn Mills and his colleagues wanted to explore whether placebo can be used to reduce withdrawal symptoms caused by abstinence from drugs. The main way in which the placebo effect is induced is by deceiving patients that the substance they are receiving has the effects researchers want to achieve (when it really does not). However, these researchers wanted to know whether a placebo that is administered openly, by informing study participants that it is a placebo, can also achieve the desired effects.
The drug they decided to work with is coffee. Coffee contains caffeine. “Caffeine is an acceptable analogue with which to model the underlying processes involved in addiction as it bears the hallmarks of all addictive substances including tolerance and a well-established withdrawal syndrome, but these are mild compared with more serious drugs,” the study authors explained.
Participants were 72 regular coffee drinkers (22 males, between 18 and 56 years of age). Each of them reported drinking 3 or more 200 milliliter cups of coffee every day. To induce the withdrawal symptoms participants were instructed not to drink coffee 24 hours before the study and told that researchers will test whether they drank coffee using saliva samples. The story about saliva samples was a deception. These samples were indeed collected to maintain the cover story, but were not really analyzed.
When they arrived at the laboratory, participants were randomly divided into three groups – deceptive, open-label and control group. All participants then completed a demographic and caffeine use questionnaire and an assessment of caffeine withdrawal symptoms (the Caffeine Withdrawal Symptom Questionnaire, CWSQ). After that, beverages were prepared in front of participants and given to them.
In this study, there were three groups of participants. The first two groups were given decaffeinated coffee, but one group (Open-Label) was told they were getting decaf, while the other group (Deceptive) was led to believe they were getting regular coffee. The third group was given water. The coffee used in the Open-Label and Deceptive groups was either in its original packaging or in fake packaging that looked like it contained regular coffee. Participants were asked to drink their coffee slowly and finish it completely.
After drinking their beverages, participants were allowed a 45-minute period to absorb the caffeine. They spent this period in the laboratory, free to study, browse the internet, or use their phones. After this period, they completed the caffeine withdrawal symptoms assessment for the second time.
Results showed that caffeine withdrawal scores decreased substantially during the experiment in the deceptive and open-label groups. The control group also recorded a reduction in symptoms, but it was negligible. The reduction was higher in the deceptive group than in the open-label group.
When participants’ expectations about the effects of different beverages on withdrawal symptoms were considered, results showed that participants expected regular coffee to have the greatest effect on reducing withdrawal symptoms, but that they also expected water to be more effective at this than decaffeinated coffee. After the experiment, participants in the deceptive groups had 10.7 times higher odds of reporting that they believe that the beverage they drank would make them feel better compared to the open-label group and 15 times higher odds than the control group.
“Though not as large as in the Deceptive group, the reduction in caffeine withdrawal in the Open-Label group was substantial and significant, suggesting that caffeine withdrawal symptoms can be reduced by placebo caffeine even when people know they are receiving placebo,” the study authors concluded.
The study contributed to the scientific knowledge about effects of placebo on drug withdrawal symptoms. However, it also has limitations that need to be taken into account. Notably, decaffeinated coffee still contains small amounts of caffeine. It is thus not a full placebo. Additionally, samples sizes were small and effects were assessed through self-reports while participants knew what the aim of the study is.
The study, “Reduction in caffeine withdrawal after open-label decaffeinated coffee”, was authored by Llewellyn Mills, Jessica C. Lee, Robert Boakes, and Ben Colagiuri.
