CHAO Tos: Codeina, HederA Helix, LevOdropropizina Para la TOS

• Codeine (Drug): Codeine 10mg/5ml + Pseudoephedrine 7.5mg/5ml + Chlorphenamine 0.5mg/5ml: 10ml three times per day during 4 days
• Levodropropizine (Drug): Levodropropizine 30mg/5ml: 10ml three times per day during 4 days
• Ivy Leaves Cough Liquid (Drug): Ivy Leaf (Hedera Helix Extract) 35 mg/5ml: 10ml three times per day during 4 days
• Placebo (Drug): Vitamins: 10ml three times per day during 4 days

Primary outcomes

• Change in cough severity [48 hours]: Change in cough severity measured by a cough numerical rating scale (0-10, higher scores mean higher cough severity)

Secondary outcomes

• Change in cough severity [4 days]: Change in cough severity measured with the cough numerical rating scale (0-10, higher scores mean higher cough severity)
• Change in cough severity [10 days]: Change in cough severity measured with the cough numerical rating scale (0-10, higher scores mean higher cough severity)
• Change in cough severity and duration [48 hours]: Change in cough severity and duration measured with the Cough Severity Diary
• Change in cough severity and duration [4 days]: Change in cough severity and duration measured with the Cough Severity Diary
• Change in cough severity and duration [10 days]: Change in cough severity and duration measured with the Cough Severity Diary
• Treatment failure [4 days]: Categorical outcome: Yes: Persisting with a score ≥6 in the cough numerical rating scale (0-10) No: Not having cough or persisting with a score <6 in the cough numerical rating scale (0-10)
• Treatment failure [10 days]: Categorical outcome: Yes: Persisting with a score ≥6 in the cough numerical rating scale (0-10) No: Not having cough or persisting with a score <6 in the cough numerical rating scale (0-10)
• Treatment safety [48 hours]: Number of adverse events
• Treatment safety [4 days]: Number of adverse events
• Treatment safety [10 days]: Number of adverse events

Sex: All, ages: 18 Years to 65 Years

Inclusion Criteria:

1. Have between 18 and 65 years of age.
2. Have an URTI with Jackson Score ≥6 points.
3. Have moderate or severe cough assessed by having a score ≥2 points in the cough domain of the Jackson Score and ≥60mm on the cough visual analogue scale (VAS).
4. Have initiated cough within 5 days of enrollment.
5. Be capable of understanding and complying with study procedures.
6. Sign a written informed consent.

Exclusion Criteria:

1. Physician considers that potential participant needs or might need to use antibiotics at the screening visit (e.g., suspected bacterial otitis, bacterial tonsilitis, bacterial sinusitis, bacterial bronchitis, or bacterial pneumonia) or suspected need for antibiotics during patient follow-up.
2. Individuals with pre-existing respiratory conditions, including asthma, chronic obstructive pulmonary disease (COPD), or any chronic lower respiratory tract disease.
3. Uncontrolled cardiovascular condition (hypertension, diabetes, etc.)
4. Contraindications to use Levodropropizine, Codeine, Pseudoephedrine, Chlorphenamine, or Ivy Leaf (Hedera Helix Extract), including Fructose Intolerance, Bronchorrhea, Kartagener Syndrome, Ciliary Dyskinesia, Respiratory Failure, Bronchial Obstructive Syndrome, severe Hypertension, Peptic Ulcer, using Monoamine Oxidase Inhibitors (MAOIs), CYP2D6 ultra-fast metabolizers.
5. Pregnancy, suspected pregnancy, desired pregnancy, or breastfeeding.
6. Contraindications to the study medications will also result in exclusion, including known or suspected allergies to Levodropropizine, Codeine, Pseudoephedrine, Chlorphenamine, or Hedera Helix Extract.
7. Known adverse reactions to Levodropropizine, Codeine, Pseudoephedrine, Chlorphenamine, or Hedera Helix Extract.
8. Participants currently using medications that could interfere with study outcomes, such as other cough suppressants, inhalers, or systemic corticosteroids.
9. Researcher considers participant might not comply with study procedures.