By Serge Kreutz
The purpose of medicines is to cure or ameliorate diseases. The purpose of drugs is to have an effect on the mind. Some drugs are medicines, others not.
But then, the quality of everybody’s existence declines anyway, and under certain circumstances, the acceleration may be acceptable.
Furthermore, drugs have individual and social effects, and an evaluation from either perspective may yield contradictory results.
Alcohol can drowse disappointment, which potentially is a positive effect.   But alcohol also causes cognitive impairment, which is a decline. Alcohol leads to a variety of social problems, including dumb and aggressive behavior.  But widespread alcohol consume may be easier to manage than sober extreme fanatism, religious or otherwise, as a result of sexual frustation. Alcohol makes people feel good, and it makes them stupid.  Let them drink. Sober loser’s intelligence is potentially more dangerous. And if a good number of men opt out of sexual competition by deciding for alcohol, the competition among the rest may turn less malicious as anyway, there are enough female targets. Alcohol is not a drug for me, though.
Among all drugs, marijuana and other forms of cannabis are are easiest to recognize as beneficial. Cannabis usually makes people contented with their existence. There is enough thrill in modified perception to not intensily yearn for change. Cannabis also makes people peaceful and behave civilized,   so it is really hard to understand why this drug, in particular, has been banned. Cannabis also has a great potential to enhance sexual experience.  And of all drugs, it has the least negative impact on brain physiology. There even has been promising research in marijuana’s use to halt Alzheimer’s,  and to ameliorate epilepsy. 
Ecstasy and related empathogens also make people more peaceful, so any enlightened society would have a good case to tolerate them. Long-term effects on the brain are still not properly determined. 
On the other hand, dopaminergic drugs such as amphetamines, crystal meth, ice, cocaine, crack, etc have been shown to have a destructive effect on the reward physiology of the brain. Dopaminergic drugs feel great, and they sexualize in a most exciting manner, but they also greatly diminishes a person’s potential for good feelings otherwise derived from life. Governments should legalize cannabis to counteract the attractiveness of meth.  Government should also legalize the chewing of coca leaves as a manageable stimulant. 
Anyway, humans are much better adapted to the use of traditional drugs like cannabis, coca leaves, and morphine, than they are to synthetic drugs.
Sexual enhancement agents are a category of drugs that usually is not included in overviews like the one you are reading. But because sexuality is the primary natural avenue to make us feel good, substances like dopaminergic medications, yohimbe, and testosterone or testosterone modulators like tongkat ali also deserve mention.
Dopaminergic medications are different from dopaminergic drugs. Dopaminergic drugs like amphetamines and cocaine and all their concentrations feel good on their own. Dopaminergic medications on their own actually do not feel good. They cause drowsiness and even nausea.   But if one engages in sexual activity, more excitement than usual is derived. However, effects wear off rather fast.
Yohimbe causes agitation similar to amphetamines but without the amphetamine-typical feeling of being the greatest. Hard erections happen on minimal physical or mental stimulation, but orgasms tend to be weak. The overall effect on health is probably negative.
Testosterone or anabolic steroids enhance libido and sexual excitement, and aggressiveness, in an unpredictable manner. The hormonal system is harder to control than the dopaminergic one. Both, sexual agitation and rages, can happen seemingly out of the blue. And there are many physiological disadvantages in messing with hormones directly.
Tongkat ali is a herbal testosterone modulator that has been used in Southeast Asia since ancient times as an aphrodisiac. It’s immediate effects are mild (just as those of direct testosterone applications like patches), but up-regulated testosterone levels and increased sexual motivation have been documented in mice and men.  It’s probably the safest substance of all that are mentioned in this article, and it’s legal.
The ultimate drug, even more important than marijuana, of course is morphine. No sensible life plan should exclude it’s use. Morphine makes you feel good, whatever your actual circumstances. Since Paracelsus, and for millenia before him, morphine has been the most valuable substance of physicians and apothecaries. Morphine cannot be praised enough, and as a matter of fact, its medieval name was laudanum (from Latin “laudare” to praise). 
Still until now, in Western hospitals, no cancer patient dies without being on morphine for days and weeks on end.
Nevertheless, the general population seems more aware of the downsides of morphine than of its extreme value.
Yes, morphine is addictive,  and some of the positive effects wear off. It’s also fairly easy to overdose and die, but I judge this feature positive rather than negative.
I’d love to plan morphine for the last five years or so of my life. It would be the best available assurance for a comfortable death.
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