ADVERSE REACTIONS
In multiple-dose United States and foreign controlled studies in which adverse reactions were reported spontaneously, adverse effects were frequent but generally not serious and rarely required discontinuation of therapy or dosage adjustment. Most were expected consequences of the vasodilator effects of Nifedipine capsules.
| Adverse Effect | Nifedipine capsules (%)
(N=226) | Placebo (%)
(N=235) |
|---|
| Dizziness, lightheadedness, giddiness | 27 | 15 |
| Flushing, heat sensation | 25 | 8 |
| Headache | 23 | 20 |
| Weakness | 12 | 10 |
| Nausea, heartburn | 11 | 8 |
| Muscle cramps, tremor | 8 | 3 |
| Peripheral edema | 7 | 1 |
| Nervousness, mood changes | 7 | 4 |
| Palpitation | 7 | 5 |
| Dyspnea, cough, wheezing | 6 | 3 |
| Nasal congestion, sore throat | 6 | 8 |
There is also a large uncontrolled experience in over 2100 patients in the United States. Most of the patients had vasospastic or resistant angina pectoris, and about half had concomitant treatment with beta-adrenergic blocking agents. The most common adverse events were:
Incidence Approximately 10%
-
- Cardiovascular: peripheral edema
-
- Central Nervous System: dizziness or lightheadedness
-
- Gastrointestinal: nausea
-
- Systemic: headache and flushing, weakness
Incidence Approximately 5%
-
- Cardiovascular: transient hypotension
Incidence 2% or Less
-
- Cardiovascular: palpitation
-
- Respiratory: nasal and chest congestion, shortness of breath
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- Gastrointestinal: diarrhea, constipation, cramps, flatulence
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- Musculoskeletal: inflammation, joint stiffness, muscle cramps
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- Central Nervous System: shakiness, nervousness, jitteriness, sleep disturbances, blurred vision, difficulties in balance
-
- Other: dermatitis, pruritus, urticaria, fever, sweating, chills, sexual difficulties
Incidence Approximately 0.5%
-
- Cardiovascular: syncope (mostly with initial dosing and/or an increase in dose), erythromelalgia
Incidence Less Than 0.5%
-
- Hematologic: thrombocytopenia, anemia, leukopenia, purpura
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- Gastrointestinal: allergic hepatitis
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- Face and Throat: angioedema (mostly oropharyngeal edema with breathing difficulty in a few patients), gingival hyperplasia
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- CNS: depression, paranoid syndrome
-
- Special Senses: transient blindness at the peak of plasma level, tinnitus
-
- Urogenital: nocturia, polyuria
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- Other: arthritis with ANA (+), exfoliative dermatitis, gynecomastia
-
- Musculoskeletal: myalgia
Several of these side effects appear to be dose related. Peripheral edema occurred in about one in 25 patients at doses less than 60 mg per day and in about one patient in eight at 120 mg per day or more. Transient hypotension, generally of mild to moderate severity and seldom requiring discontinuation of therapy, occurred in one of 50 patients at less than 60 mg per day and in one of 20 patients at 120 mg per day or more.
Very rarely, introduction of Nifedipine capsules therapy was associated with an increase in anginal pain, possibly due to associated hypotension. Transient unilateral loss of vision has also occurred.
In addition, more serious adverse events were observed, not readily distinguishable from the natural history of the disease in these patients. It remains possible, however, that some or many of these events were drug related. Myocardial infarction occurred in about 4% of patients and congestive heart failure or pulmonary edema in about 2%. Ventricular arrhythmias or conduction disturbances each occurred in fewer than 0.5% of patients.
In a subgroup of over 1000 patients receiving Nifedipine capsules with concomitant beta blocker therapy, the pattern and incidence of adverse experiences were not different from that of the entire group of Nifedipine capsules treated patients. (See PRECAUTIONS.)
In a subgroup of approximately 250 patients with a diagnosis of congestive heart failure as well as angina pectoris (about 10% of the total patient population), dizziness or lightheadedness, peripheral edema, headache, or flushing each occurred in one in eight patients. Hypotension occurred in about one in 20 patients. Syncope occurred in approximately one patient in 250. Myocardial infarction or symptoms of congestive heart failure each occurred in about one patient in 15. Atrial or ventricular dysrhythmias each occurred in about one patient in 150.
In post-marketing experience, there have been rare reports of exfoliative dermatitis caused by nifedipine. There have been rare reports of exfoliative or bullous skin adverse events (such as erythema multiforme, Stevens-Johnson Syndrome, and toxic epidermal necrolysis) and photosensitivity reactions. Acute generalized exanthematous pustulosis also has been reported.
