What do online pharmacies have to offer? From an analysis of the literature it appears that online pharmacies have become more and more complex as time passes; whereas 10 years ago they tended to sell principally lifestyle drugs such as sildenafil, it looks today as if they offer virtually anything. Back in 1999, Bloom and Iannacone [61] studied a sample of online pharmacies in which the majority sold 1 or 2 drugs only, one for erectile dysfunction and the other for alopecia; in the same year Armstrong et al [57] found an entire sample of 77 websites selling sildenafil. In 2003 Arruanda [58] found that their sample was equally divided into 3 groups: selling 1 drug only, between 2 and 29 drugs (average 7), and selling 30 or more. The various studies reported several specific drug offers: sildenafil [59,60,80,84,86,87], benzodiazepines [84,86,87], painkillers [80,84,88], antibiotics [87,88], insulin [87,88], female hormones [87,88], antidepressants [80,84,86], alopecia medications [14,27,80], and obesity medications [59,80]. Bloom and Iannacone [62] reported that 160 separate medications were offered in their sample, which gives an idea of how widely differentiated the drug offer is. Quon et al [89] compared the offers of 12 Canadian-based Internet pharmacies with 3 US-based drug chain pharmacies for 44 different drugs. The GAO [73] found that some drugs were more widely available and easier to purchase (Celebrex, Lipitor, Viagra, and Zoloft) than others, which were available from fewer sources or were more difficult to obtain (Accutane and Clozaril). As we will see in more detail in the next section on actual purchase, what is hard to obtain—despite appearing to be available—is US class II and III opioid analgesics, as found in Peterson and colleagues’ studies in 2001 [87] and 2003 [88] and confirmed by the GAO 2004 [73]. In the United States, “Under the Controlled Substances Act all substances that are regulated under existing federal law are placed in one of five schedules on the basis of the substances’ medicinal value, harmfulness, and potential for abuse or addiction. Schedule I is reserved for the most dangerous drugs that have no recognized medical use, while Schedule V is the classification used for the least dangerous drugs.” [72]. The NABP [10] survey showed that 14% of websites dispensed controlled substances as defined by the Act cited above, and 40% foreign or non-FDA-approved drugs.
Some studies focused on specific classes of drugs. They looked for Parkinson disease medications [95], 3 types of controlled substances (opioids, and central nervous system depressants and stimulants) [63], opiates [64,67-70]), analgesics [90], dextropropoxyphene (a painkiller) [91], antibiotics [82], and specifically ciprofloxacin [93], contraceptives [83], the erectile dysfunction medication sildenafil [57,66,71], and psoriasis medications [81].
Littlejohn et al [80] and Makinen et al [27] linked the drugs offered to the type of online pharmacy: “legitimate pharmacies” did not supply opioids or ritalin [80], selling only over-the- counter products and herbal, hygiene, and cosmetic products [27]; “lifestyle pharmacies” supplied erectile dysfunction and alopecia medications; and “no-prescription pharmacies” supplied virtually everything, including opioids [80] and unapproved pharmaceuticals [27]. Both generic and brand drugs were available on the market [14,58,79,89,95].