Nifedipine Peak Concentration Time

## Time to Peak Concentration (Tmax) of Nifedipine The time to peak plasma concentration (Tmax) of nifedipine varies substantially depending on the **dosage formulation**: ### Immediate-Release Capsules - **Tmax**: Approximately **30 minutes** after oral administration; drug is detectable in serum as early as 10 minutes [5] - Peak blood levels occur at approximately 30 minutes [5] ### Extended-Release Tablets The Tmax differs across branded extended-release formulations: | Formulation | Tmax | Notes | |-------------|------|-------| | **Nifedipine Extended-Release Tablets (generic)** | ~**6 hours** (plateau reached) | Plasma concentrations rise gradually and reach a plateau at approximately 6 hours after the first dose [1][4] | | **Afeditab CR / Adalat CC** | **2.5–5 hours** (first peak); second small peak at **6–12 hours** | Biphasic absorption profile [2][3] | | **Adalat CC (broader reference)** | **2.5–6 hours** | Peak plasma concentrations attained within this window [6] | ### Key Clinical Implications - **Formulation-dependent variability**: The Tmax for extended-release tablets (2.5–6 hours) is substantially longer than for immediate-release capsules (~0.5 hours), reflecting the controlled-release design intended to minimize peak-to-trough fluctuations [1][2][3][4] - **Food effect**: A high-fat meal increases the peak concentration (Cmax) by approximately 60% and prolongs Tmax for extended-release tablets, though total AUC remains unchanged [2][3] - **Biphasic profile**: Afeditab CR and Adalat CC exhibit a characteristic biphasic pattern with an initial peak at 2.5–5 hours followed by a secondary shoulder at 6–12 hours, likely due to the extended-release matrix design [2][3] --- *This information is derived from retrieved drug labels and pharmacokinetic references. Clinicians should verify specific product labeling for the prescribed formulation and consider individual patient factors (e.g., hepatic impairment, GI transit time) that may alter absorption kinetics.*