Budesonide (budesonide)

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There is no enhanced messaging for this drug.

There are no contraindication interactions for this drug.

Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

Agents That Affect Iodide/Radioactive Iodide

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(2) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(3)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1)

Agents That Affect Iodide/Sodium Iodide I 131

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1,2)

CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1,2)

PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less.

PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1,2) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(3) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(4)

DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1,2)

Selected Sensitive Cyp3a4 Substrates/Oral Lefamulin

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Lefamulin is considered a moderate inhibitor of CYP3A4. FDA defines a moderate inhibitor as a drug which increases the area-under-curve (AUC) of a sensitive substrate by 2- to 5-fold.(1,3)

CLINICAL EFFECTS: Concurrent use of oral lefamulin may lead to increased serum levels and adverse effects of drugs sensitive to inhibition of the CYP3A4 pathway.(1)

PREDISPOSING FACTORS: With darifenacin, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(4)

PATIENT MANAGEMENT: If oral lefamulin must be coadministered with a sensitive CYP3A4 substrate, it is recommended to closely monitor for adverse effects of the CYP3A4 substrate.(1) Drug-specific recommendations: The manufacturer of abemaciclib recommends monitoring for adverse reactions and considering a dose reduction of abemaciclib in 50 mg decrements as detailed in prescribing information (based on starting dose, previous dose reductions, and combination or monotherapy use) with concurrent use of moderate CYP3A4 inhibitors.(2)

DISCUSSION: In a study, oral lefamulin tablets administered concomitantly with and at 2 or 4 hours before oral midazolam (a CYP3A4 substrate) increased the area-under-curve (AUC) and maximum concentration (Cmax) of midazolam by 200% and 100%, respectively. No clinically significant effect on midazolam pharmacokinetics was observed when co-administered with lefamulin injection.(1) Sensitive CYP3A4 substrates linked to this monograph include: abemaciclib, acalabrutinib, alprazolam, atorvastatin, brotizolam, budesonide, buspirone, cobimetinib, darifenacin, ebastine, eletriptan, elvitegravir, everolimus, lovastatin, lurasidone, maraviroc, midazolam, nisoldipine, paritaprevir, sildenafil, simvastatin, ticagrelor, triazolam, and ulipristal.(1,3,5)

Selected Steroids/Antiretroviral Cyp3a4 Inhibitors

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Antiretroviral CYP3A4 inhibitors may inhibit the metabolism of corticosteroids metabolized by CYP3A4. Dexamethasone may induce metabolism of agents that are substrates of CYP3A4.(1-13,50)

CLINICAL EFFECTS: Concurrent use of antiretroviral CYP3A4 inhibitors may result in increased systemic exposure to and effects from corticosteroids metabolized by CYP3A4, including Cushing's syndrome and adrenal suppression. Concurrent dexamethasone may result in decreased levels and effectiveness of CYP3A4 substrates.

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: If possible, avoid concurrent therapy of corticosteroids metabolized by CYP3A4 with antiretroviral CYP3A4 inhibitors. Alternative corticosteroids that are less affected by CYP3A4 inhibitors should be considered, like beclomethasone, prednisone, and prednisolone. If concurrent therapy is warranted, patients should be closely monitored for systemic effects. The corticosteroid may need to be discontinued. Patients receiving concurrent therapy with dexamethasone and substrates of CYP3A4 should also be monitored for decreased effectiveness of the CYP3A4 substrate. The manufacturers of nasal fluticasone(14-16) and fluticasone for inhalation(17) state that concurrent use of fluticasone and atazanavir, indinavir, nelfinavir, ritonavir or saquinavir is not recommended. The US manufacturers of atazanavir,(1) fosamprenavir,(5) indinavir(6) and nelfinavir(8) recommend caution with concurrent use of inhaled or nasal fluticasone. Consider alternatives to fluticasone if long-term use is required.

DISCUSSION: In a study, boceprevir (800 mg TID for 7 days) increased the area-under-curve (AUC) of a single dose of prednisone (40 mg) by 22%. The maximum concentration (Cmax) and AUC of prednisolone increased by 16% and 37%, respectively.(2) A study of 14 healthy adults found that concurrent use of ketoconazole with ciclesonide increased the AUC of ciclesonide's active metabolite, des-ciclesonide, by approximately 3.6-fold at steady state, while levels of ciclesonide remained unchanged. However, the study concluded that no dosage adjustments were required because ciclesonide has a very low potential to cause side effects.(18) A study in 18 healthy subjects examined the effects of ritonavir (100 mg twice daily) on fluticasone nasal spray (200 mcg daily). In most subjects, fluticasone was undetectable (<10 pg/ml) when administered alone. In subjects in whom fluticasone was detectable when given alone, Cmax and area-under-curve AUC averaged 11.9 pg/ml and 8.43 pg x hr/ml, respectively. With concurrent ritonavir, fluticasone Cmax and AUC increased to 318 pg/ml and 3102.6 pg x hr/ml, respectively.(7,11,14) This reflects increases in Cmax and AUC by 25-fold and 350-fold, respectively.(3) The cortisol AUC decreased by 86%.(6,14-16) In a study in 10 healthy subjects, ritonavir (200 mg twice daily for 4 and 14 days) increased the AUC of a single dose of prednisolone by 1.41-fold and 1.30-fold, respectively, after 4 days and 14 days of ritonavir.(19) There have been several case reports of Cushing's syndrome in patients treated concurrently with ritonavir and inhaled budesonide,(19-20) dexamethasone,(22) injectable triamcinolone,(23-26) nasal fluticasone.(28-46) Hepatitis has also been reported with concurrent budesonide and ritonavir.(47) In a study in 9 healthy subjects, mibefradil (50 mg once daily for 3 days) increased the AUC, Cmax, and elimination half-life of methylprednisolone by 3.8-fold, 1.8-fold, and 2.7-fold, respectively.(48) In a study in 8 healthy subjects, following nefazodone administration the following changes were seen with methylprednisolone: mean (+/-SD) area under the concentration-time curve was significantly higher (1393 +/- 343 vs. 2966 +/- 928 ug*h/L; P < 0.005), apparent clearance was lower (28.7 +/- 7.2 vs. 14.6 +/- 7.8 L/h; P < 0.02) and the terminal elimination half-life was longer (2.28 +/- 0.49 vs. 3.32 +/- 0.95 hours; P < 0.02).(49) Selected steroids metabolized by CYP3A4 are linked to this monograph.(50) Selected CYP3A4 inhibitors and substrates linked to this monograph include: atazanavir, cobicistat, darunavir, fosamprenavir, indinavir, lenacapavir, lopinavir, nelfinavir, saquinavir, and tipranavir.(50)

Selected Steroids/Selected Strong Cyp3a4 Inhibitors

SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction.

MECHANISM OF ACTION: Strong CYP3A4 inhibitors may inhibit the metabolism of corticosteroids metabolized by CYP3A4.

CLINICAL EFFECTS: Concurrent use of strong CYP3A4 inhibitors may result in increased systemic exposure to and effects from corticosteroids metabolized by CYP3A4, including Cushing's syndrome and adrenal suppression.

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: If possible, avoid concurrent therapy between corticosteroids metabolized by CYP3A4 and strong CYP3A4 inhibitors. Alternative corticosteroids that are less affected by CYP3A4 inhibitors should be considered, like beclomethasone, prednisone, and prednisolone. If concurrent therapy is warranted, patients should be closely monitored for systemic effects. The corticosteroid may need to be discontinued.

DISCUSSION: In a study, boceprevir (800 mg TID for 7 days) increased the area-under-curve (AUC) of a single dose of prednisone (40 mg) by 22%. The maximum concentration (Cmax) and AUC of prednisolone increased by 16% and 37%, respectively.(3) A study of 14 healthy adults found that concurrent use of ketoconazole with ciclesonide increased the AUC of ciclesonide's active metabolite, des-ciclesonide, by approximately 3.6-fold at steady state, while levels of ciclesonide remained unchanged. However, the study concluded that no dosage adjustments were required because ciclesonide has a very low potential to cause side effects.(4) A study in 18 healthy subjects examined the effects of ritonavir (100 mg twice daily) on fluticasone nasal spray (200 mcg daily). In most subjects, fluticasone was undetectable (<10 pg/ml) when administered alone. In subjects in whom fluticasone was detectable when given alone, Cmax and area-under-curve AUC averaged 11.9 pg/ml and 8.43 pg x hr/ml, respectively. With concurrent ritonavir, fluticasone Cmax and AUC increased to 318 pg/ml and 3102.6 pg x hr/ml, respectively.(6-8) This reflects increases in Cmax and AUC by 25-fold and 350-fold, respectively.(6) The cortisol AUC decreased by 86%.(10-13) In a study in 10 healthy subjects, ritonavir (200 mg twice daily for 4 and 14 days) increased the AUC of a single dose of prednisolone by 1.41-fold and 1.30-fold, respectively, after 4 days and 14 days of ritonavir.(14) There have been several case reports of Cushing's syndrome in patients treated concurrently with ritonavir and inhaled budesonide,(15-16) dexamethasone,(17) injectable triamcinolone,(18-21) nasal fluticasone.(23-41) Hepatitis has also been reported with concurrent budesonide and ritonavir.(42) In a study in 9 healthy subjects, mibefradil (50 mg once daily for 3 days) increased the AUC, Cmax, and elimination half-life of methylprednisolone by 3.8-fold, 1.8-fold, and 2.7-fold, respectively.(43) In a study in 8 healthy subjects, following nefazodone administration the following changes were seen with methylprednisolone: mean (+/-SD) area under the concentration-time curve was significantly higher (1393 +/- 343 vs. 2966 +/- 928 ug*h/L; P < 0.005), apparent clearance was lower (28.7 +/- 7.2 vs. 14.6 +/- 7.8 L/h; P < 0.02) and the terminal elimination half-life was longer (2.28 +/- 0.49 vs. 3.32 +/- 0.95 hours; P < 0.02).(44) Selected steroids metabolized by CYP3A4 are linked to this monograph.(45) Selected CYP3A4 inhibitors linked to this monograph include: adagrasib, boceprevir, ceritinib, clarithromycin, erythromycin, itraconazole, josamycin, ketoconazole, lonafarnib, mibefradil, nefazodone, paritaprevir, posaconazole, ribociclib, telaprevir, telithromycin, troleandomycin, tucatinib, and voriconazole.(1-2,45)

Moderate Interaction: Assess the risk to the patient and take action as needed.

Selected Corticosteroids/Levoketoconazole

SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed.

MECHANISM OF ACTION: Levoketoconazole may inhibit the CYP3A4 mediated metabolism of some corticosteroids, resulting in increased systemic exposure. Levoketoconazole may also suppress endogenous cortisol output. Levoketoconazole is the enantiomer of ketoconazole.

CLINICAL EFFECTS: Concurrent use of levoketoconazole may result in elevated levels of and effects from the corticosteroid, including Cushing syndrome. These effects have been seen with systemic as well as inhaled corticosteroids.

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: Patients should be carefully monitored with concurrent administration of these agents, or when levoketoconazole is added to corticosteroid therapy. The dose of the corticosteroid may need to be adjusted or alternative therapy considered.

DISCUSSION: The concurrent use of ketoconazole has been shown to increase budesonide area-under-curve (AUC) by eight-fold. In a study in eight healthy subjects, the simultaneous administration of ketoconazole increased budesonide AUC by 6.5-fold. Administering the two agents 12 hours apart increased budesonide AUC by 3.8-fold. In a study in 6 healthy subjects, pretreatment with ketoconazole (200 mg daily) increased the AUC of a single intravenous dose of methylprednisolone (20 mg) by 135% and decreased its clearance by 60%. Concurrent ketoconazole also increased the reduction in 24-hour cortisol AUC and suppressed morning cortisol concentrations. In a study in 8 healthy subjects, ketoconazole decreased the clearance of methylprednisolone by 46% and increased mean residence time by 37%. In a randomized, cross-over study in 6 healthy subjects, pretreatment with ketoconazole (200 mg daily for 6 days) had no effect on the pharmacokinetics of a single intravenous dose of prednisolone (14.8 mg). In a study, concurrent oral ketoconazole increased the AUC of des-ciclesonide from orally inhaled ciclesonide by 3.6-fold. There were no changes in ciclesonide levels. In a study in 24 healthy subjects, subjects were randomized to receive either ketoconazole (200 mg BID) or placebo on Days 4-9 of a a 9 day course of mometasone (400 mcg BID). No subject had mometasone levels greater than 150 pcg/ml on Day 3. Four of 12 subjects who received ketoconazole had mometasone Cmax levels greater than 200 mcg/ml on Day 9. Plasma cortisol levels appeared to decrease as well. In a cross-over study in 15 healthy subjects, subjects were randomized to receive fluticasone furoate and vilanterol on days 5-11 with either ketoconazole (200mg once daily) or placebo for days 1-11 with a washout period of 7-14 days. Fluticasone furoate AUC was increased by 36%, Cmax was increased by 33%, and decreased systemic cortisol levels by 27%. There were no effects on heart rate and blood potassium levels. There was a small increase in QTc which was 7.6ms greater when compared to placebo; however, ketoconazole has been reported to increase QTc by 5-6ms. Vilanterol AUC was increased by 65% and Cmax was increased by 22%. There were no effects on heart rate and blood potassium levels. No serious adverse events occurred and no subjects withdrew from the study due to adverse events. The most common adverse event reported was headache. Coadministration of orally inhaled fluticasone (1000 mcg) and ketoconazole (200 mg once daily) resulted in a 1.9-fold increase in plasma fluticasone exposure and a 45% decrease in plasma cortisol AUC.

Selected Sensitive Cyp3a4 Substrates/Schisandra

SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed.

MECHANISM OF ACTION: Schisandra is considered a moderate inhibitor of CYP3A4. FDA defines a moderate inhibitor as a drug which increases the area-under-curve (AUC) of a sensitive substrate by 2- to 5-fold.(1,2)

CLINICAL EFFECTS: Concurrent use of Schisandra may lead to increased serum levels and adverse effects of drugs sensitive to inhibition of the CYP3A4 pathway.(3-7)

PREDISPOSING FACTORS: With darifenacin, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(8)

PATIENT MANAGEMENT: If Schisandra must be coadministered with a sensitive CYP3A4 substrate, it is recommended to closely monitor the CYP3A4 substrate and adjust its dose as appropriate.(3-7) The US manufacturer of sirolimus protein-bound injection (Fyarro) states a dose reduction to 56 mg/m2 is recommended when used concurrently with moderate or weak CYP3A4 inhibitors. Concurrent use with strong CYP3A4 inhibitors should be avoided.(8)

DISCUSSION: A study in 12 healthy volunteers found that Schisandra led to an increase in midazolam area-under-curve (AUC) and maximum concentration (Cmax) of 2.05- and 1.65-fold, respectively, compared to midazolam administered alone.(3) In a study of 18 healthy volunteers, sirolimus AUC and Cmax increased by 2.07-fold and 1.96-fold, respectively when given with Schisandra compared to sirolimus administered alone.(4) The effect of Schisandra on tacrolimus has been examined in several small pharmacokinetic studies in healthy volunteers as well as liver and kidney transplant patients. Compared to tacrolimus given alone, tacrolimus AUC when administered with Schisandra was consistently increased by 2.1-fold, while the increase in Cmax varied between 1.83- and 2.11-fold in the transplant studies(5-6) and 3-fold in the study on healthy subjects.(7) In the study with kidney transplant patients, a decrease in tacrolimus dose of 40.9 % was required to bring tacrolimus levels into the therapeutic range.(5)

Selected Steroids/Ensitrelvir; Nirmatrelvir-Ritonavir

SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed.

MECHANISM OF ACTION: Ensitrelvir and nirmatrelvir/ritonavir may inhibit the metabolism of corticosteroids metabolized by CYP3A4.(1,2)

CLINICAL EFFECTS: Ensitrelvir and nirmatrelvir/ritonavir may result in increased systemic exposure to and effects from corticosteroids metabolized by CYP3A4.(1,2)

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: Coadministration with corticosteroids of all routes of administration of which exposures are significantly increased by strong CYP3A4 inhibitors can increase the risk of Cushing's syndrome and adrenal suppression. However, the risk of Cushing's syndrome and adrenal suppression associated with short-term use of a strong CYP3A4 inhibitor is low.(1) The manufacturer of nirmatrelvir/ritonavir recommends considering alternative corticosteroids including beclomethasone, prednisone, and prednisolone.(1)

DISCUSSION: Concurrent use of a single dose of midazolam 2 mg, a CYP3A4 substrate, with nirmatrelvir-ritonavir (300 mg/100 mg twice daily for nine doses) increased the maximum concentration (Cmax) and area-under-curve (AUC) of midazolam by 37% and 143%, respectively.(1) A study in 18 healthy subjects examined the effects of ritonavir (100 mg twice daily) on fluticasone nasal spray (200 mcg daily). In most subjects, fluticasone was undetectable (<10 pg/ml) when administered alone. In subjects in whom fluticasone was detectable when given alone, Cmax and area-under-curve AUC averaged 11.9 pg/ml and 8.43 pg x hr/ml, respectively. With concurrent ritonavir, fluticasone Cmax and AUC increased to 318 pg/ml and 3102.6 pg x hr/ml, respectively.(7,11,13) This reflects increases in Cmax and AUC by 25-fold and 350-fold, respectively.(3) The cortisol AUC decreased by 86%.(4-7) In a study in 10 healthy subjects, ritonavir (200 mg twice daily for 4 and 14 days) increased the AUC of a single dose of prednisolone by 1.41-fold and 1.30-fold, respectively, after 4 days and 14 days of ritonavir.(8) In a clinical study, ensitrelvir (750 mg on day 1 and 250 mg on days 2-5) increased the Cmax and AUC of dexamethasone 1 mg single dose by 1.47-fold and 3.47-fold, respectively.(2) Selected steroids linked to this monograph include: budesonide, ciclesonide, dexamethasone, fluticasone, methylprednisolone, and triamcinolone.(9)

Known hypersensitivity to budesonide or any ingredient of the formulation.

There are no contraindication contraindications for this drug.

• Nasal septal perforation
• Nasal septal ulcers
• Nasal trauma
• Ocular herpes simplex
• Ocular hypertension
• Open angle glaucoma
• Operation on nose
• Severe infection

• Adrenocortical insufficiency
• Cataracts
• Epistaxis
• Inactive tuberculosis
• Parasitic infection

Adverse effects of budesonide occurring in 2% or more of patients receiving budesonide nasal spray and with an incidence more frequent than that of placebo include epistaxis, pharyngitis, bronchospasm, cough, and nasal irritation.

Less Frequent

• Crusted nasal mucosa
• Epistaxis
• Lesion of nasal mucosa
• Lethargy
• Sore throat

Rare or Very Rare

• Contact dermatitis
• Nasal candidiasis
• Nasal septal perforation
• Ocular hypertension
• Pharyngeal candidiasis
• Skin rash
• Urticaria

More Frequent

• Dry nose
• Nasal passage irritation

Less Frequent

• Sneezing

No enhanced messaging available.

Safety and efficacy of intranasal budesonide have not been established in children younger than 6 years of age. Intranasal corticosteroids may cause growth suppression in children or adolescents, and clinicians should routinely monitor (e.g., via stadiometry) the growth of pediatric patients receiving these drugs. See Cautions: Pediatric Precautions, in the Corticosteroids General Statement 68:04.

Category C. (See Users Guide.) Hypoadrenalism may occur in infants of mothers receiving corticosteroid therapy during pregnancy. These infants should be carefully monitored.

Not known whether budesonide is distributed in milk. Caution is advised if the drug is administered in nursing women.

Although no overall differences in safety and efficacy were observed between geriatric and younger patients, frequency of epistaxis appears to increase with age. In addition, the possibility that some older individuals may exhibit increased sensitivity to the drug cannot be ruled out.