Opiates

Methadone: Oral 84%. Elimination half-life:24-36 hours, 

Ketobemiodone: Oral 34% +/-10%; Rectal 44% +/- 9%. Elimination half-life: 2.25- 2.45 hours

Meperidine: Rectal 55%, IM 80-85% Elimination half-life 3.0 h

Buprenorphine: Oral 22%; Sublingual 30%; IM 90-100%. Elimination half-life: 12-44 hours

Hydromorphone: Oral-30-35%; Intranasal 52.4%; Rectal 33%

Dihydrocodeine: Oral 20%. Elimination halflife 4 hours

Heroin: Oral 35%; IM 85% 

Fentanyl: Transdermal 92%; Sublingual and Buccal 50%; Intranasal 70%. Protein binding 80-85% Elimination half-life 3-12 hours

Sufentanil: Intranasal 78%,

Remifentanil: Protein binding 70%. Elimination half-life 1-20 minutes 

Alfentanil: 92% Protein binding. Elimination half-life is 1.5-2 hours

Morphine: Oral 30%; Rectal 30%; Intranasal 15-20%, Chitosan(a linear polysaccharide that helps absorb drugs better) has been shown to increase nasal bioavailability of morphine from around 10-20% to over 60%, SC-60%, protein binding 30-40%, half-life is 2-3 hours

Oxycodone: Oral 60-87%; intranasal- 55-70% 

Hydrocodone: Oral bioavailability is not really known but it is around oxycodone bioavailability; Orally 70% of it is usually absorbed, half-life is 4-8 hours

Oxymorphone: Intranasal 43%; Orals 10-20%; Rectal 10%

BUTORPHANOL : Oral 5-17% 

Tramadol: Oral 68-72%; Rectal 77%: Eliminatio half-life 5-7 hours 

Codeine: Oral 90%; Rectal 90%

Diphenoxylate: Protein binding 74-95%. Elimination half-life 12-14 hours 

Pethidine(meperidine): Oral 50-60%. Protein Binding 65-75%, Half Life 3-5 hours 

Normeperidine Is about half as potent as meperidine, but it has twice the CNS stimulation effects. 

Pentazocine: Oral 20%. Half-life 2 to 3 hours