CAN DILTIAZEM BE USED AS A ROUTINE ADJUVANT IN PATIENTS WITH HYPERTHYROIDISM

Objective: To assess the possibility of using diltiazem as a routine adjuvant drug in hyperthyroidism by evaluating
the effects of combined therapy of diltiazem and carbimazole on the adrenergic manifestations of hyperthyroidism
and thyroid function tests, and to compare these effects with those of combination of propranolol and carbimazole.
Material and methods: This prospective, interventional study included 45 newly diagnosed patients of hyperthy-
roidism attending the out patient department of Institute of Radiotherapy and Nuclear Medicine, Peshawar. Patients
were randomised to two groups. Patients in group I (n = 20, male/female ratio 2:18, mean age: 41.75 + 11.13 years)
took diltiazem 30 mg + carbimazole 10 mg three times a day for 6 weeks. Patients in group II (n = 25, male/female
ratio 4:21, mean age: 37.72 + 8.90 years) took propranolol 20 mg + carbimazole 10 mg three times daily for 6 weeks.
Clinical assessment was done before starting therapy and then after 6 weeks (+ 3days) using standardised and
modified hyperthyroid symptom score (HSS). Biochemical assessment was done by measuring serum FT4
in the
beginning and then after 6 weeks (+ 3 days) of starting therapy.
Results: In group I, FT4
decreased from 38.43 ± 6.67 to 34.30 ± 6.50 after 6 weeks of therapy with diltiazem and
carbimazole (p < 0.001). HSS decreased from 15.80 ± 2.35 to 8.25 ± 2.53 (p < 0.001). In group II, FT4
decreased from
37.47 ± 7.75 to 34.21 ± 7.89 after 6 weeks of therapy with propranolol and carbimazole (p < 0.001). HSS decreased
from 14.88 ± 2.01 to 8.36 ± 1.91 (p < 0.001). Mean decline in FT4
in group I (4.12 ± 3.19) when compared with mean
decrease in FT4
in group II (3.21 ± 3.47), the difference was non-significant (p > 0.05). Similarly, mean decrease in
HSS in group I (7.55 ± 2.11) when compared with mean decline in HSS in group II (6.52 ± 1.92), the difference was
non-significant (p > 0.05).
Conclusion: Combination of diltiazem and carbimazole is as effective as the combination of propranolol and
carbimazole. As there are very few clinical limitations of diltiazem as compared to propranolol, it can be used as a
routine adjuvant drug in the management of hyperthyroidism.
Key words: Diltiazem, propranolol, carbimazole, hyperthyroidism, adrenergic manifestations, free T4
concentration.