Mental health medication in the climate crisis

Climate change affects how medication works

Sixty-five million Americans (one in five) take mental health medications, and the number is rising. The most common medications that doctors prescribe for their patients are for anxiety and depression. While climate change may cause more people to take mental health medication, climate change and extreme heat may make those medications work less well

Medications may not work as effectively when stored at higher temperatures, as could happen when the earth gets hotter. Often, pharmacies keep medications at low temperatures to prevent this from happening, but pharmacies may not always be able to keep things cool. Furthermore, hotter weather and dehydration both make it more likely for these drugs to cause potentially dangerous side effects when people take them.

Unequal impacts

Depending on the number of medications and types of medications that someone is taking, the likelihood of potentially dangerous side effects changes considerably.

People with serious mental illness such as schizophrenia, schizoaffective disorder, or bipolar disorder, as well as people who are on more than one medication, are at a high risk of worsened side effects in hot weather. There is evidence that people with schizophrenia, even without medicines, are already at higher risk for having potentially deadly high body temperatures (hyperthermia), so adding the effect that medicine has to raise body temperature can make the risks of taking them even worse

Climate change, in addition to causing worsened side effects, may also make getting medication more difficult. The creation, transportation, and delivery of medications may be disrupted. And of course people who don’t have medical insurance, or good enough medical insurance, or who otherwise have difficulty getting mental health care, are at higher risk. 

People who are taking medicine that leaves their body more quickly, and people with serious mental illness, may be in the most danger of having new symptoms and illness if they stop being able to get their medicine in a climate disaster, even if they were previously in a stable mental condition. 

When patients become sick, it affects their ability to get their medications and become well. People with schizophrenia, bipolar disorder, or dementia are more likely to have problems making their way to the pharmacy when they are not doing well. People who take certain medications for anxiety such as alprazolam (Xanax), lorazepam (Ativan), and clonazepam (Klonipin) may go into life-threatening withdrawal.

Consequences if we don’t reduce carbon emissions drastically

Given that hotter weather makes medications not work as well, and that extreme weather makes delivery, transportation, and creation of medications more challenging, people with mental illness may experience a worsening of their illness or even experience life-threatening side effects. 

Studying heat’s effect on mental health medications alone is difficult, if not impossible, as heat itself has many effects on mental health in and of itself. It is likely that the effect of heat on medications adds to increased patient suffering, emergency room visits, psychiatric and medical hospital stays, and strain on the system of mental healthcare.

Research findings

Multiple classes of medications are affected by extreme heat and dehydration.

  • Hotter body temperatures can occur for people who take antipsychotic medications (used for schizophrenia, bipolar disorder, and other conditions) such as olanzapine (Zyprexa), risperidone (Risperdal), or haloperidol (Haldol). 
  • High body temperatures and overheating can also occur when people take other types of mental health medication. These medications treat multiple kinds of mental illness, and include:
    • Antidepressants used for depression, anxiety, and/or chronic pain such as mirtazapine (Remeron), amitriptyline (Elavil, Endep, Vanatrip), and nortriptyline (Pamelor, Aventyl HCl).
    • Anxiety medications such as hydroxyzine (Vistaril, Atarax, Rezine).
    • Specific over-the-counter sleep medications and diphenhydramine used for sleep (found in Benadryl, Allermax, Banophen, Diphedryl, Sominex, Aleve PM, and others) can be risky, or even lethal, in extreme heat.
  • Several antidepressants, some sleep medications such as trazodone (Desyrel, Oleptro) or doxepin, and pain medications called opioids can cause increased sweating, which makes dehydration more likely.
  • Dehydration can raise drug levels of lithium and mood stabilizers leading to illness and side effects.
    • People who use substances such as alcohol and MDMA, or ecstasy, are already more likely to become dehydrated .
  • Patients taking certain anxiety medications need to be careful that they could withdraw and even die if they cannot get their medication in extreme weather. These medications include alprazolam (Xanax, Niravam), lorazepam (Ativan, Loreev XR), and clonazepam (Klonipin).

Next directions for research

Research still needs to be done on exactly how the climate crisis will impact mental health medication, including research on our newest medications.

Addressing medication effects

  • Given that the amount of medication in the blood may not stay steady in hotter weather, physicians may choose to check laboratory tests for drug levels or kidney function. One example of a drug level that should be checked is lithium. 
  • It may make sense for some people on mental health medications to have a larger amount of medication on hand, especially those with schizophrenia, bipolar disorder, or anxiety (specifically those on medications where they can withdraw). This is often a risk-and-benefit decision. Having large amounts of medication could be risky for people who suffer from substance abuse or who have attempted suicide by overdose, depending on the medication and circumstances.
  • Physicians should discuss having emergency substance withdrawal kits with patients taking certain medications or who have substance use disorders.

Further reading

Online Sources

National Institute of Mental Health patient information, including side effects of common mental health medications

Storing Medications: Why You Have to Take Special Precautions During the Summer

Scientific Press

Woodward, B. (2019). Climate Disruption and the Psychiatric Patient. Psychiatric Times, 36(3).

Wortzel, J. and Haase, E. (2020, April 14). The Effects of Rising Global Temperatures on Mental Health. Psychiatric News.

Selected Research/Scientific Papers

Cusack, L., de Crespigny, C., & Athanasos, P. (2011). Heatwaves and their impact on people with alcohol, drug and mental health conditions: a discussion paper on clinical practice considerations. Journal of Advanced Nursing, 67(4), 915–22.

Galea, S., Tracy, M., Norris, F., & Coffey, S. F. (2008). Financial and social circumstances and the incidence and course of PTSD in Mississippi during the first two years after Hurricane Katrina. Journal of Traumatic Stress, 21(4), 357–368.

Berko, J., D. D. Ingram, S. Saha, & Parker, J. D.. (2014). Deaths Attributed to Heat, Cold, and Other Weather Events in the United States, 2006–2010. National Health Statistics Reports, 30(76),1-15.

Martin-Latry, K., M. P. Goumy, P. Latry, C. Gabinski, B. Bégaud, I. Faure, & Verdoux, H.. (2007). Psychotropic drugs use and risk of heat-related hospitalisation. European Psychiatry, 22(6), 335-338.

Author and version info

September 22, 2022
Author: Tova Fuller, MS MD PhD, Psychiatrist
Editor: Rei Takver