An important consideration is that the opinion of heroin smokers may conflict with the laboratory assessment of actual heroin content. In a laboratory measurement heroin content can be reliably established. However, the 'bioavailability' (and thus the perceived effects) for smokers is dependent on a number of other factors, such as heroin form, processing impurities or diluents." Heroin is either marketed in the salt (usually the hydrochloride) form or as the base. The salt dissolves easily in water and can thus be injected without other additions, while the base does not. But when pure heroin hydrochloride is heated on aluminum foil the major part does not volatilize, but degrades, mostly by charring. When smoked, only a small part of this heroin is actually absorbed by the body. There are indications that only 15-20% of the heroin hydrochloride becomes available when careful smoking is performed. Rough heating (poor chasing technique) may result in even more charring. 17 (table 3.4)
It is, however, not impossible to smoke the salt form. The percentage of heroin hydrochloride that volatilizes, and is thus ingested, is strongly dependent on the admixed compounds. A large increase in volatilization is observed when caffeine is added. Caffeine was traditionally mixed in on a ± 1 + 1 basis in the South East Asian no.3 heroin. (table 3.4) The recipe, which is known from the beginning of this century, was designed for smoking.` 18 19 20 Until 1980 most illicit heroin in the Netherlands came from SEA and usually in the hydrochloride form. (table 3.3) For smoking purposes this hydrochloride form was not optimal, but the choice for caffeine as an admixture was a logical one. 90% of samples encountered on the Dutch heroin market before 1980 were of this composition.
From 1980 on SWA heroin dominated the Dutch illicit market. This product has seldom been found as the hydrochloride salt; the base form prevailed.16 For that reason, IDUs add an acidifier to make an injectable solution. In contrast with the salt, heroin base is quite effective on smoking. it volatilizes much better -under laboratory conditions ±60% of the heroin base is recovered, which is about three to four times as much as for the salt form. 16 However, illegally processed South West Asian heroin base also contains many diluents and processing impurities. (table 3.5) These compounds influence the volatilization of heroin to a great extent. The most important admixture in the beginning of the 1980s, procaine hydrochloride, causes a strong degradation, reducing bio-availability to about 12%. A 1 + 1 mixture of heroin base with ascorbic acid results in a nearly complete degradation of heroin in the smoking process. Ascorbic acid is infrequently found in heroin samples seized abroad, but with a few exceptions not in the Netherlands. Likewise, the high noscapine levels in the product since 1985 may have also reduced heroin's bioavailability for smokers. 16 The diluent paracetamol, important in 1989, 1990 and 1991 has a strong negative influence on the bio-availability when heroin is smoked. in the smoking process heroin reacts with the paracetamol, forming a less active compound. A partly compensation is obtained by the caffeine which is often found in combination with paracetamol. 15 22 At the other hand, caffeine and other admixed compounds, such as barbital and methaqualone facilitate volatilization, whereas some diluents have little effect and seem just added to enlarge the volume. The compounds most frequently encountered in seized heroin generally enhance volatilization. (table 3.5)
Finally, the temperature and heating technique are of considerable influence. Experience with the chasing technique is important, as adding too much heat results in charring and degradation into weaker or inactive compounds." These effects indicate a complex relation between the heroin content and the effects as experienced by the smoker, whereas IDUs' experiences may show a more or less linear relation regarding the strength of the heroin." However, their experience of the drug effects may also be influenced by the admixed compounds, e.g. procaine is rumored to increase the rush or impact effect.
- besides he fucked me over by making me drive for shit that fell through, the prick). 