Table 6.
pKa values, maximum dose, and salt forms of some BCS II weak acids.
| Compound | pKa values | Maximum dose (mg) | Acid/salt form | Provisional BCS classification |
|---|---|---|---|---|
| Acetyl-salicylic acid | 3.5 (47) | 975 | Free acid | BCS I or III |
| Atorvastatin | 4.46 (47) | 80 | Calcium salt | BCS II (48) |
| Diacerein | 4.74* | 50 | Free acid | non-us marketed drug |
| Diclofenac | 4.2 (49) | 50 | K and Na salts | BCS II |
| Diflunisal | 3.0 (47) | 500 | Free acid | BCS II |
| Etodolac | 4.7 (47) | 400 | Free acid | BCS II |
| Epalrestat | 3.2* | 50 | Free acid | non-us drug |
| Fenoprofen | 4.5 (49) | 600 | Calcium salt | BCS II |
| Flurbiprofen | 4.3 (49) | 100 | Free acid | BCS II |
| Fluvastatin | 4.76* | 40 | Na salt | BCS II |
| Furosemide | 3.88, 9.37* | 80 | Free acid | BCS II |
| Ibuprofen | 4.4 (49) | 800 | Free acid | BCS II |
| Indomethacin | 4.5 (49) | 50 | Free acid | BCS II |
| Ketoprofen | 4.76 (49) | 75 | Free acid | BCS II |
| Ketorolac | 3.5 (49) | 20 | Tromethamine salt | Salt form: BCS I |
| Mefenamic acid | 4.2 (47) | 250 | Free acid | BCS II |
| Meloxicam | 1.1, 4.2 (50) | 15 | Free acid | BCS II |
| Naproxen | 500 | Free acid | Acid: BCS II (51) | |
| 4.2 (49) | 500 | Na salt | Na salt: BCS I (52) | |
| Oxaprozin | 4.3 (50) | 600 | Free acid | BCS II |
| Piroxicam | 1.8, 5.1 (50) | 20 | Free acid | BCS II |
| Salicylic acid | 3.0 (47) | 750 | Free acid | BCS I |
| Sulindac | 4.5 (49) | 200 | Free acid | BCS II |
| Triflusal | 4.15* | 300 | Free acid | non-us drug |
| Tolmetin (53) | 3.5 (49) | 600 | Na salt | BCS II |
| Zaltoprofen | 4.44* | 80 | Free acid | non-us drug |
| Warfarin | 5.35* | 10 | Na salt (54) | BCS I |
*
calculated using Program ADMET version 1.2.3,