diphenhydramine is typically found in benadryl in 25mg per pill, but if you live in the uk or have access somehow to get these, you should try Nytol, 50mg of Diphenhydramine hydrochloride and there are 16 pills in a packet and on Amazon they cost only £2.89. Dosage varies and usually 200mg/800mg is a good dosage, but 600mg for a beginner is great. You should know beforehand that taking diphenhydramine at a recreational dosage WILL make you hallucinate (unless its something from 200mg/300mg) but im guessing that's what your trying to achieve :D. You need to be in the right state of mind, because some of these hallucinations can be horrible. Most common hallucinations are of spiders, or cockroaches surrounding you or on you so if your afraid of bugs best avoid. DO NOT drive or ride a bike, or go-kart, or whatever, its dangerous and puts others in danger too. You might get problems with vision, and with your coordination and your judgement is flawed. Many consider the hours your on diphenhydramine to be like schizophrenia, also its been compared to alcohol and LSD or weed. You should have a friend, one who is tolerant with your behaviour, because if you start to have a bad hallucination you need someone there to reassure you that your on drugs and not (insert bad hallucination). Just a couple more things, you may forget you have taken drugs (some people report this, another reason to have a friend), also, go onto http://www.erowid.org/pharms/diphenhydramine/diphenhydramine.shtml
. Erowid is a great site for getting more info and has experiences that other people have had, its not an 'anti-drug' website rather a place where you can get unbiased information on drugs. To finish off, its great experimenting with drugs just as long as you are careful and know what to do, Im currently waiting on some Nytol (cause im underage :P) so im in the same situation as you, hope this helped!