ISOSORBIDE DINITRATE/MONONITRATE
Brand names [Dinitrate] Cedocard, Imtack, Isoket, Isordil, Soni-slo, Sorbichew, Sorbid SA, Sorbitrate; [Mononitrate] Elantan,Imdur, Ismo, Isotrate, MCR-50, Monit, Mono-Cedocard
General Information
Isosorbide dinitrate and mononitrate are vasodilator drugs similar to glyceryl trinitrate. They are usually used to treat patients suffering from angina, and are also used in some cases of heart failure.
Unlike glyceryl trinitrate, however, both forms of isosorbide are stable and can be stored for long periods without losing their effectiveness.
Headache, flushing, and dizziness are common side effects during the early stages of treatment; small initial doses of the drug minimize these symptoms. The effectiveness of isosorbide dinitrate and mononitrate may be reduced after a few months; if this occurs, an alternative treatment may need to be considered.
Information for Users
Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.
How taken
Dinitrate Tablets (held under the tongue, chewed, or swallowed), SR-tablets, SR-capsules, injection, spray. Mononitrate Tablets, SR-tablets, SR-capsules.
Frequency and timing of doses
Relief of angina attacks Tablets chewed or held under the tongue, or spray, as needed (certain preparations only). Prevention of angina 2-4 x daily;
1-2 x daily (SR-tablets, capsules).
Adult dosage range
Relief of angina attacks 5-10mg per dose. Prevention of angina 30-120mg daily.
Onset of effect
2-3 minutes when chewed or held under the tongue or used as spray (certain preparations only); 30 minutes when swallowed.
Duration of action
Up to 2 hours (chewed); up to 5 hours (swallowed); up to 10 hours (SR-capsules).
Diet advice
None.
Storage
Keep in a closed container in a cool, dry place out of the reach of children. Protect from light.
Missed dose
Take as soon as you remember. If your next dose is due within 2 hours, take a single dose now and skip the next.
Stopping the drug
Do not stop taking the drug without consulting your doctor; stopping the drug may lead to worsening of the underlying condition.
Exceeding the dose
An occasional unintentional extra dose is unlikely to cause problems. Large overdoses may cause dizziness and headache. Notify your doctor.
Possible Adverse Effects
The most serious adverse effect is excessively lowered blood pressure, and this may need to be monitored on a regular basis. Other adverse effects of both forms of the drug usually improve after regular use; dose adjustment may help.
Interactions
Antihypertensives
A further lowering of blood pressure occurs when such drugs are taken with isosorbide dinitrate.
Quick Reference
Drug group Nitrate vasodilator and anti-angina drug
Overdose danger rating Medium
Dependence rating Low
Prescription needed Yes
Available as generic Yes
Special Precautions
Be sure to tell your doctor if:
You have long-term liver or kidney problems.
You have any blood disorders or anaemia.
You have had glaucoma.
You are taking other medications.
Pregnancy
Safety in pregnancy not established. Discuss with your doctor.
Breast-feeding
Safety not established. Discuss with your doctor.
Infants and children
Not usually prescribed.
Over 60
No special problems.
Driving and hazardous work
Avoid such activities until you have learned how isosorbide dinitrate or mononitrate affects you because these drugs can cause dizziness.
Alcohol
Avoid. Alcohol may further lower blood pressure, depressing the heart and causing dizziness and faintness.
Prolonged Use
The initial adverse effects may disappear with prolonged use. The effects of the drug become weaker as the body adapts, requiring increased dosage or other drugs.
