modelR03DA20
Extends from Pharmacokinetic.Models.PK_1C_enteral.
Information
| name: | CombinationsOfXanthines | |
| ATC code: | R03DA20 | route: | oral |
| compartments: | 1 | |
| dosage: | 240 | mg |
| volume of distribution: | 0.5 | L |
| clearance: | 0.04 | L/kg/h |
| other parameters in model implementation | ||
Combinations of xanthines, such as theophylline with other bronchodilators (for example, etofylline or diprophylline), are used primarily in the management of asthma and chronic obstructive pulmonary disease (COPD) to relax bronchial smooth muscle and relieve bronchospasm. These combinations have been largely replaced by newer agents but may still be used in some countries for specific patient populations.
Pharmacokinetics
Pharmacokinetic parameters were estimated based on the combination of theophylline and etofylline in adults after oral administration. Model parameters are adapted from standard theophylline PK studies in adults (mean values in healthy subjects), as no direct publication for the exact combination was found.
References
Zandvliet, AS, et al., & Beijnen, JH (2005). Population pharmacokinetics of caffeine and its metabolites theobromine, paraxanthine and theophylline after inhalation in combination with diacetylmorphine. Basic & clinical pharmacology & toxicology 96(1) 71–79. DOI:10.1111/j.1742-7843.2005.pto960111.x PUBMED:https://pubmed.ncbi.nlm.nih.gov/15667599
Straka, RJ, et al., & Walker, PF (1996). Predominance of slow acetylators of N-acetyltransferase in a Hmong population residing in the United States. Journal of clinical pharmacology 36(8) 740–747. DOI:10.1002/j.1552-4604.1996.tb04244.x PUBMED:https://pubmed.ncbi.nlm.nih.gov/8877679
Koren, G, et al., & MacLeod, SM (1985). Theophylline pharmacokinetics in adolescent females following coadministration of oral contraceptives. Clinical and investigative medicine. Medecine clinique et experimentale 8(3) 222–226. PUBMED:https://pubmed.ncbi.nlm.nih.gov/4042465
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Mass | weight (from PK_1C) | 75 | patient weight (kg) |
| Modelica.Units.SI.SpecificVolume | VdPerKg (from PK_1C) | 0.9 | Volume of distribution (L/kg) |
| Modelica.Units.SI.MassFraction | F (from PK_1C) | 0.8 | bioavailiability (0-1) |
| Pharmacolibrary.Types.Clearance | Cl (from PK_1C) | 20 | clearance |
| Modelica.Units.SI.Time | adminTime (from PK_1C) | 60 | first administration time (s) |
| Modelica.Units.SI.Time | adminDuration (from PK_1C) | 600 | administration duration (s) |
| Modelica.Units.SI.Time | adminPeriod (from PK_1C) | 8*60*60 | period of administration (default 8 hours)(s) |
| Pharmacolibrary.Types.Mass | adminMass (from PK_1C) | 1000 | administration mass (mg) |
| Integer | adminCount (from PK_1C) | 8 | number of dose administered (1) |
| Pharmacolibrary.Types.Volume | Vd (from PK_1C) | VdPerKg*weight | Volume of distribution (m3) |
| Pharmacolibrary.Types.MassConcentration | Cmin (from PK_1C) | 0.004 | minimal therapeutic range |
| Pharmacolibrary.Types.MassConcentration | Cmax (from PK_1C) | 0.008 | minimal therapeutic range |
| Pharmacolibrary.Types.MassConcentration | Ctox_peak (from PK_1C) | 0.012 | toxicity peak level |
| Pharmacolibrary.Types.MassConcentration | Ctox_trough (from PK_1C) | 0.006 | toxicity trough level |
| Pharmacolibrary.Types.TransferRate | ka (from PK_1C_enteral) | 0.016666666666666666 | first order absorption rate |
| Modelica.Units.SI.Time | Tlag (from PK_1C_enteral) | 600 | delay between oral administration and absorption (default 10min) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Types.ConcentrationOutput | C_central (from PK_1C) | ||
| Interfaces.ConcentrationPort_b | centralCPort (from PK_1C) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Pharmacokinetic.NoPerfusedTissueCompartment | central (from PK_1C) | ||
| Pharmacokinetic.ClearanceDrivenElimination | elim (from PK_1C) | ||
| Sources.PeriodicDose | periodicDose (from PK_1C) | ||
| Modelica.Units.SI.Time | t1_2 (from PK_1C) | elimination half-life |
Revisions
- 06/2025 Tomas Kulhanek, generated model from data extracted from PUBMED, DrugBank and LLM(GPT4.1)