1. Methamphetamine Reduces Human Influenza A Virus Replication
I have heard anecdotally that in-fact, there is some concrete scientific support for its treating of the COVID catastrophe.
It would make some sense in that if it is capable of preventing the replication or rate of increase of pupolation of this virus...

2. METHAMPHETAMINE DIFFERENTIALLY AFFECTS BDNF AND CELL DEATH FACTORS IN ANATOMICALLY DEFINED REGIONS OF THE HIPPOCAMPUS
Methamphetamine increases BDNF expression and thereby reduces cell death.

3. Is Cognitive Functioning Impaired in Methamphetamine Users? A Critical Review
No cognitive impairment was identified in the methamphetamine users compared to controls.

4. Methamphetamine Induces Low Levels of Neurogenesis in Striatal Neuron Subpopulations and Differential Motor Performance
Shows an overall (net) cell growth over a perod of twelve weeks following a humongous injection of methamphetamine. But also shows that overall the proportion of the new cells is low compared to the ones which died by apoptosis. It is my opinion that actually this substance is not as neurotoxic as it is made out to be as amphetamine and also methamphetamine are inherently quite nontoxic. It is that there is much misinformation being promulgated even in scientific literature today. This is due to private interest groups with ulterior motives who wish to form social conceptions and things which are untrue to reality to generate some cognitive bias amongst the people. I am currently trying to find more appropriate studies which better represent the truth about methamphetamine.

5. Long-term Antipsychotic Treatment and Brain Volumes
Antipsychotic (antidopaminergic type) treatment reduced brain volumes.

6. Treatment of Childhood Schizophrenia Utilizing LSD and Psilocybin
Cancelled studies from the '60s that involved giving many high doses of psychedelics to young children with schizophrenic symptoms, showing an improvement in their life quality, to the point that children who couldn’t attend school were able to after the treatments.

7. Psychedelics and Mental Health: A Population Study
"According to a new study published PLOS One [linked to above], there is no link between the use of psychedelic drugs—specifically LSD, psilocybin, mescaline, and peyote—and a range of mental health problems. In fact, the study reports, psychedelic use is associated with a lower risk of mental health problems like psychosis, anxiety disorders, mood disorders, and general psychological distress."

8. Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis
A study which shows the effects of some of the chemical species in cannabis on cancerous cells.

9. Life span extension in Drosophila melanogaster induced by morphine
This study states to show the anti-ageing effects of morphine, and thus also heroin (diacetylmorphine), on the body.