Be careful.

So we're told not to take drugs, they're bad. But people do. I'm not going to say you should, or should not. I'm just going
to say something omitted by mainstream thought, in the interests of harm reduction.

Drugs, at least in their illegal market, are not safe, you don't know what you're getting. That said this advice might reduce the harm
caused by them... I'm not saying this alone will make you safe when taking them, but it might help...

Mdma:
Don't overheat:
I met a guy at heaven in Charing cross (gay club, i'm straight, interesting crowd).
He was wearing his jumper and jacket, in the middle of a hot dance floor, and on mdma.
I persuaded him to give me his jumper and jacket, he felt cold, and was at risk of overheating.

Test your drugs:
Get a Marquis agent testing kit , it changes colour based on your substance.

Google your pills:
Each has a stamp, google mdma + the logo. Is there any negative press about it?

Don't sell:
Even to your friends, it's not worth the prison time.

Don't buy in clubs:
You have no idea who it's coming from, or their intentions.

Don't overhydrate or underhydrate:
Drink water, not too much, a pint every now and then.

IF you feel unwell at a festival:
Ask stewards for festival welfare, they will look after you.

LSD:

The New Scientist magazine did a brain scan of someone tripping.

This is your mind on acid, it's 0 to 60 miles an hour in 5 seconds. It opens doorways in the mind which will never close.
My logic on it as to why some people are fine on acid and some are not is this...
if you can go through the doorways in your mind it will be ok, otherwise you will crash.
I got spiked at a party and suffered serious mental health problems for years afterwards. I've seen people burn out on it.
Then again i think it rewired my brain. it's a harsh task-master, it will turn your world upside down, inside out etc.

*IF* you're going to do this:
Be in an environment you control.
Have a trip sitter who isn't on anything.
Have some CBD oil to hand.

Cocaine:
Often mixed with crack, be careful on this one. Very moreish and it fuels your ego, which can give confidence, or make you act like a complete idiot.