Which of the following routes of administration are suitable for nitroglycerine?
(A) P,R,S
(B) P,Q,R
(C) P,Q,S
(D) R,S
One category of the antianginal agents produce a side effect commonly known as Monday morning sickness. Select the drug that produces above side effect.
(A) Calcium channel blockers
(B) Potassium channel activators
(C) Nitro vasodilators
(D) All of the above
Nitro vasodilators release nitric oxide which can cause vasodilatation of vascular smooth muscle. This may result in few of side effects like headache, tachycardia, dizziness etc. Since this Page of side effects were observed in workers on Monday after drug free period during Sunday, the symptoms are termed as Monday morning sickness.
Uncoated nitroglycerine tablets are orally ineffective because
(A) High first pass metabolism
(B) Irritant to gastric mucosa
(C) Unstable at gastric pH
(D) All of the above
Nitrogylcerine has high first pas metabolism. Hence it is ineffective by oral route. It is generally given by sublingual and transdermal route. Now nitroglycerine sustained release products are available which has long duration of action as well as have less first pass metabolism hence can be taken orally.
The unwanted effect of nitrovasodilators is
(A) Convulsions
(B) Diarrhea
(C) Orthostatic hypotension
(D) Hepatitis
The main unwanted effect is orthostatic hypotension and throbbing headache. They can also produce light headedness, flushing and other vasodilatory response.
Nitro vasodilators show
(A) Dependence
(B) Addiction
(C) Tolerance
(D) All of the above
One of the important limitation of the nitrovasodilators is their tolerance. Organic nitrates when used for long period develop tolerance towards their vasodilatory effects. This may be due to decreased release of nitric oxide from organic nitrates due to depletion of thiol groups in the tissues or due to any alteration in cGMP activity. The tolerance can be prevented by nitrate-free intervals. Hence long acting organic nitrates should be give 12-hour nitrate free interval to restore their activity.