Felodipine Compared to Nifedipine as "Third-Line Drug" in Resistant Hypertension

Abstract

Felodipine is a new dihydropyridine calcium antagonist, and in hypertension it is a much more effective "third-line" drug than hydralazine. Nifedipine, on the other hand, is the established dihydropyridine calcium antagonist that has been increasingly used to treat hypertension. Information is now needed on the relative merits and demerits of these two drugs. This study appraised, therefore, the therapeutic utility of twelve months' treatment with nifedipine 20-60 mg twice daily in 55 patients with previous drug-resistant hypertension who had been successfully treated for the previous year with felodipine 5-20 mg twice daily, each calcium antagonist being used in combination with atenolol 100 mg daily with or without chlorthalidone 25 mg daily. Initially, nifedipine maintained comparable blood pressure control to that which had been achieved by felodipine, although in the longer term (over eight months) nifedipine proved less effective than felodipine had (p less than 0.02) and more patients became uncontrolled (supine diastolic blood pressure, Phase V, greater than or equal to 90 mmHg) on the maximum tolerated dose of the calcium antagonist (chi 2 = 4.13, p less than 0.05 greater than 0.025). The former degree of blood pressure control was, however, reestablished by increasing the dose of nifedipine or reintroducing the diuretic as necessary, and this control was maintained over the next four months. Minor side effects were less common on nifedipine than they had been during the preceding felodipine treatment phase. Felodipine thus has more pronounced and sustained antihypertensive effects than nifedipine, though its side effect burden may appear to be greater.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of indomethacin on the pharmacokinetics and pharmacodynamics of felodipine.

“…The side-effects for felodipine (headache, flushing) and indomethacin (headache, gastrointestinal complaints) were frequent compared with placebo. This is consistent with observations in clinical trials where minor adverse effects from felodipine can be experienced in a relatively high percentage of a study population (Maclean et al, 1986). However, indomethacin appeared to diminish the flushing effect of felodipine.…”

Atenolol‐nifedipine combinations compared to atenolol alone in hypertension: efficacy and tolerability.

“…Symptomatic hypotension may occur occasionally when the combination therapy is used instead of monotherapy (Opie et al, 1982). Others have reported some loss of nifedipine's efficacy in the longer term, even in combination with a P-adrenoceptor blocker, and this may necessitate the addition diuretic to restore BP control (Lederballe Pedersen et al, 1980;Maclean et al, 1986), but our study design restricted assessment to short-term efficacy.…”