Injecting - downer of some sort?

[JaWill88]

are there any intravenously injectable downers available such as a benzodiazepine, a barbituate, a muscle relaxer... whatever? swim is pretty sure benzos can be used in hospitals intravenously as they have a solution made or whatever but swim could be wrong. are/were there intra injectable barbituates or muscle relaxers? what about methaqualone (quaalude) or meprobamate (miltown). has anyone had any experience with intrav injected downers? swim really liked heroin intravenously and thought the rush to be the most incredible feeling in the world (but unfortunately brought on terrible addiction). but anyways swim always thought something like benzos would produce a nice feeling intravenously injected. unfortunately swim has never had the chance to try barbs and methaqualone and things like that. are/ there any commercially available downers (aka Central Nervous System Depresants) for intravenous injection? what about intramuscular? anyone have any info or even better, personal experience?