Description
Formal competitive model shift with supplied equilibrium parameters.
A pharmacodynamic model relates an exposure or occupancy measure to a response under explicitly supplied parameters. Baseline, maximum increment, half-maximal concentration, effect direction, and observation windows have distinct meanings. Evaluating one model term does not fit the curve or establish its clinical validity.
Formal competitive model shift with supplied equilibrium parameters.
When to use this tool
Use PD Competitive Antagonist Dose Factor Term when you need this particular response-model term, scale conversion, panel duration, or support calculation.
How to use the tool and how it works
- Enter antagonist, inhibitionConstant, agonistEc50. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read doseRatio, shiftedEc50. Use the output convention below.
For nonnegative antagonist and positive inhibitionConstant and agonistEc50 return doseRatio=1+antagonist/inhibitionConstant and shiftedEc50=agonistEc50*doseRatio.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| antagonist | Nonnegative antagonist concentration matching inhibitionConstant units. | Required. Finite number; minimum 0. |
| inhibitionConstant | Positive supplied competitive-binding concentration constant. | Required. Finite number; strictly above 0. |
| agonistEc50 | Agonist Ec50 | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| doseRatio | Dose Ratio | Required. Finite number. |
| shiftedEc50 | Shifted Ec50 | Required. Finite number. |
{
"input": {
"antagonist": 2,
"inhibitionConstant": 1,
"agonistEc50": 4
},
"output": {
"doseRatio": 3,
"shiftedEc50": 12
}
}Limitations and assumptions
- Antagonist and inhibition constant need matching concentration units. This assumes the stated ideal competitive-antagonism relation rather than fitting binding data, verifying a mechanism, or suggesting medication dosing.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Use a fitted and validated response model when a supplied local term is insufficient. Check exposure units, response direction, baseline, model assumptions, and observation support before comparing effects.
References
Similar or alternative tools
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