Paradoxical reaction
A paradoxical reaction (or paradoxical effect) is an effect of a
Paradoxical reactions may be more common in people with ADHD.[1]
Substances
Amphetamines
Amphetamines are a class of psychoactive drugs that are stimulants. Paradoxical drowsiness can sometimes occur in adults.[2] Research from the 1980s popularized the belief that ADHD stimulants such as amphetamine have a calming effect in individuals with ADHD, but opposite effects in the general population.[3] New research however disputes this claim, suggesting that ADHD stimulants have similar effects in adults with and without ADHD.[4][5]
Antibiotics
The paradoxical effect or Eagle effect (named after Harry Eagle, who first described it) refers to an observation of an increase in survivors, seen when testing the activity of an antimicrobial agent.[6] Initially when an antibiotic agent is added to a culture media, the number of bacteria that survive drops, as one would expect. But after increasing the concentration beyond a certain point, the number of bacteria that survive, paradoxically, increases.
Antidepressants
In a minority of cases, antidepressants can lead to violent thoughts of suicide or self-harm, as observed in some patients during and after treatment, which is in marked contrast to their intended effect.[7] A 1991 study found that children and adolescents were more sensitive to paradoxical reactions of self-harm and suicidal ideation while taking fluoxetine (commonly known as Prozac).[8] This can be regarded as a paradoxical reaction but, especially in the case of suicide, may in at least some cases be merely due to differing rates of effect with respect to different symptoms of depression: If generalized overinhibition of a patient's actions enters remission before that patient's dysphoria does and if the patient was already suicidal but too depressed to act on their inclinations, the patient may find themself in the situation of being both still dysphoric enough to want to commit suicide but newly free of endogenous barriers against doing so.[citation needed]
Antipsychotics
These may be more common in elderly dementia patients. Apparent worsening of dementia may be due to the anticholinergic side effects of many antipsychotics.[10]
Barbiturates
Phenobarbital can cause hyperactivity in children. This may follow after a small dose of 20 mg, on condition of no phenobarbital administered in previous days.[11] Prerequisity for this reaction is a continued sense of tension. The mechanism of action is not known, but it may be started by the anxiolytic action of the phenobarbital.
Barbiturates such as pentobarbital have been shown to cause paradoxical hyperactivity in an estimated 1% of children, who display symptoms similar to the hyperactive-impulsive subtype of attention deficit hyperactivity disorder. Intravenous caffeine administration can return these patients' behaviour to baseline levels.[12]
Benzodiazepines
Paradoxical rage reactions due to benzodiazepines occur as a result of an altered level of consciousness, which generates
Paradoxical effects of benzodiazepines appear to be dose related, that is, likelier to occur with higher doses.[16]
In a letter to the
Self aggression has been reported and also demonstrated in laboratory conditions in a clinical study. Diazepam was found to increase people's willingness to harm themselves.[18]
Benzodiazepines can sometimes cause a paradoxical worsening of
Caffeine
Caffeine is believed by many to cause paradoxical calmness or sedation in individuals with ADHD.[20] There is insufficient evidence to determine if sedation caused by caffeine is due to a true paradoxical reaction, or rather from dehydration and sleep deprivation caused by the caffeine.[21] Furthermore there are no conclusive studies showing a different effect of caffeine on individuals with ADHD compared to the general population.
Naltrexone
Naltrexone blocks the opioid receptors, acting opposite to most opioid pain medications.[22] It can be used to negate the effects of opioid painkillers. At doses around one-tenth of the typical dose, naltrexone has been used for pain relief. Low-dose naltrexone is believed to have an anti-inflammatory effect. This is an off label use and not widely accepted by the medical and scientific community.[23]
Diphenhydramine
Causes
The mechanism of a paradoxical reaction has as yet (2019) not been fully clarified, in no small part due to the fact that signal transfer of single
There are, however, multiple indications that paradoxical reactions upon – for example – benzodiazepines, barbiturates, inhalational anesthetics, propofol, neurosteroids, and alcohol are associated with structural deviations of GABAA receptors. The combination of the five subunits of the receptor (see image) can be altered in such a way that for example the receptor's response to GABA remains unchanged but the response to one of the named substances is dramatically different from the normal one.
See also
References
- PMID 21886668.
- S2CID 26068007.
- PMID 3656119.
- S2CID 36283770.
- S2CID 24320882.
- PMID 18871882.
- PMID 2301661.
- PMID 2016219.
- ^ Chlorpromazine - Adverse Effects- Behavioral Reactions[permanent dead link]
- ISSN 1098-3015.
- ^ "Professional Health Care Providers". Epilepsy Foundation.
- S2CID 19473461.
- PMID 16087304.
- PMID 8262890.
- PMID 7618826.
- from the original on 2012-12-13. Retrieved 2007-04-18.
- PMID 234269.
- S2CID 20629702.
- PMID 7403357.
- )
- ISSN 0362-4331. Retrieved 2023-01-15.
- ISBN 978-0-19-092019-7, retrieved 2023-01-15
- S2CID 16191753.
- ^ "Diphenhydramine: drowsy (sedating) antihistamine". nhs.uk. 2018-09-21. Retrieved 2024-01-11.
- ^ "Why It's Time to Rethink Our Use of Benadryl". www.nationwidechildrens.org. Retrieved 2024-01-11.
- ^ Shubailat, Nadine. "Benadryl Baby: Should You Give Allergy Drugs to Calm Kids Before Flying?". ABC News. Retrieved 2024-01-11.
- S2CID 10856872.