Two medicines, side by side
Ketoconazole vs theophylline
Ketoconazole is labeled for fungal infections; theophylline for asthma. Their labels share no use, so they are not alternatives to each other. Drugs@FDA records approvals of ketoconazole since 1981 and of theophylline since 1982. Pharmacies paid $0.249 per gram (Ketoconazole 2% cream) and $0.330 per theophylline ER 300 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. Theophylline's other strengths are brand-only: $3.82 per Theo-24 ER 100 mg capsule. In FDA's classes, ketoconazole is an azole antifungal and theophylline a methylxanthine.
Check it at the source: the ketoconazole FDA label on DailyMed (effective January 28, 2026); the theophylline FDA label on DailyMed (effective March 10, 2026).
Highlights of the ketoconazole record
Ketoconazole (Nizoral) · label of January 28, 2026
Used for
From the label: indicationsKetoconazole Cream 2% is indicated for the topical treatment of tinea corporis, tinea cruris and tinea pedis caused by Trichophyton rubrum, T. mentagrophytes and Epidermophyton floccosum; in the treatment of tinea (pityriasis) versicolor caused by Malassezia furfur (Pityrosporum orbiculare); in the treatment of cutaneous candidiasis caused by Candida spp. and in the treatment of seborrheic dermatitis.
On the market
- Earliest approval on file
- June 12, 1981
- Generic labelers
- 30 labelers
- Pharmacy cost
- $0.249 per gram
Supply and safety
- Shortage
- No current entry
- Recalls
- 3
Highlights of the theophylline record
Theophylline (Theo) · label of March 10, 2026
Used for
From the label: indicationsTheophylline extended-release tablets are indicated for the treatment of the symptoms and reversible airflow obstruction associated with chronic asthma and other chronic lung diseases, e.g., emphysema and chronic bronchitis.
On the market
- Earliest approval on file
- July 26, 1982
- Generic labelers
- 26 labelers
- Pharmacy cost
- $0.330 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 4
Source: FDA drug labels via openFDA (Ketoconazole label of January 28, 2026, Theophylline label of March 10, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do ketoconazole and theophylline differ on the record?
In FDA's classes, ketoconazole is an azole antifungal and theophylline a methylxanthine.
Generics: ketoconazole since 1999; theophylline since 1976 (Drugs@FDA).
| Ketoconazole | Theophylline | |
|---|---|---|
| Labeled for | Fungal infections | Asthma |
| Pharmacologic class | Azole Antifungal | Methylxanthine |
| How it works (label) | n/a | Mechanism of Action: Theophylline has two distinct actions in the airways of patients with reversible obstruction; smooth muscle relaxation (i.e., bronchodilation) and suppression of the response of the airways to stimuli (i.e. … |
| Half-life (label) | n/a | At steady-state, on a dosage regimen with 6-hour intervals, the expected mean trough concentration is approximately 60% of the mean peak concentration, assuming a mean theophylline half-life of 8 hours. |
| Earliest approval on file (Drugs@FDA) | June 12, 1981 | July 26, 1982 |
| First generic approved | June 15, 1999 | July 26, 1976 |
| Generic labelers (NDC) | 30 labelers | 26 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.249 per gram (Ketoconazole 2% cream) | $0.330 per tablet (Theophylline ER 300 mg tablet) |
| 12-month price change | -11% | -33% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 3 | 4 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 17,282 | 12,327 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
Do their labels mention each other?
Theophylline label, drug interactionsketoconazole; tocainide
Source: FDA drug labels via openFDA
What next?
- Alternatives to ketoconazole
- every medicine labeled for the same conditions