Dihydergot

Generic Name: Dihydroergotamine mesylate
Product Name: Dihydergot

Indication

Dihydergot is used to relieve migraine and cluster headache. It is also used to treat severe disabling orthostatic hypotension.

Action

Dihydergot contains the active ingredient dihydroergotamine. It belongs to a group of medicines known as the “ergot alkaloids.” Dihydergot has complex pharmacological effects. It has both the stimulating and blocking effects on both alpha-adrenergic and serotonergic receptors.

During migraine attacks, the small blood vessels in your brain swell and cause temporary change in size. This results in pain and visual disturbance. Dihydergot stops the atack by causing the blood vessels to shrink back to its original size. Dihydergot is only used to treat migraine attacks. It is not used to prevent attacks from happening.

Dihydergot is also used in adults to prevent a sudden, sharp drop in blood pressure that happens in some people when they stand up after sitting or lying down for a long period of time. This condition, called orthostatic hypotension, can cause severe, disabling attacks of dizziness and lightheadedness, sometimes with fainting.

Dose advice

Dose Information

Dihydergot is available as an injection and in tablet form.

How much Dihydergot is given

Acute migraine attack: Oral dihydroergotamine is not recommended for acute migraine attack because efficacy has not been demonstrated.

Severe disabling low blood pressure in adults: the first dose of Dihydergot is usually given by slow injection into a vein. After that, 1/2 to 1 tablet can be taken three times a day. If neccessary, the dose is adjusted weekly depending on your clinical response. Doses of up to 40 to 60 mg a day may be needed for some people. When treatment is needed for a prolonged period, it may be possible to reduce the daily dose.

Children under 12 years. One-third to two-thirds of the adult dosage according to age.

Important notes

1. Do not use sumatriptan, naratriptan or zolmitriptan or any medicine containing ergot alkaloids (e.g. Cafergot or Ergodryl) at the same time as you have Dihydergot. You must wait at least 24 hours before you use any other medicine containing ergot alkaloids, sumitriptan, naratriptan or zolmitriptan.
2. Do not have more than the maximum recommended daily and weekly doses of Dihydergot. Do not continue treatment for longer than your doctor recommends.
3. If you forget to take the tablets, you may take your missed dose as soon as you remember if it is more than 4 hours until your next dose is due. Otherwise, you should skip the missed dose. Then, you may take your next dose as per normal. Do not take a double dose to make up for the one that you missed as this may increase the chance of you getting an unwanted side effect.
4. Do not use Dihydergot to prevent a migraine attack from happening. This medicine should only be used to treat a migraine once it has started.
5. Avoid drinking grapefruit juice while you are having Dihydergot. Grapefruit juice may interfere with the action of Dihydergot in your body.
6. Dihydergot may make you feel dizzy. You should avoid driving, operating machinery or doing jobs that require you to be alert until you know how Dihydergot affects you.

Contraindications

Before you have Dihydergot, you must ensure that you do not 

• have allergic reaction to dihydroergotamine, the active ingredient in Dihydergot  and any other ergot alkaloids (for instance, Cafergot, Deseril, Ergodryl, Ergometrine, Kripton, Parlodel, Syntometrine)
• have heart problems such as uncontrolled angina, heart attack and severe high blood pressure
• have poor blood circulation or other blood vessel disorders
• suffer from severe liver disease
• have any serious infection
• take ketoconazole, itraconazole, erythromycin or clarithromycin
• take HIV/AIDS drugs (such as ritonavir, nelfinavir, indinavir or delvaridine)

Precautions

Before you start to have it, you must inform your doctor

• if you have liver problems or severe kidney problems as your doctor may want to take special precautions during your treatment.
• if you smoke as nicotine in cigarettes may increase the chance of you experiencing excessive constriction of blood vessels, an unwanted effects called “ergotism”.
• if you are lactose intolerant as dihydergot tablets contain lactose.
• if you are taking other medicines, including herbal supplements and over-the-counter medicines that you can obtain from pharmacy, supermarket or health food shops. You may need to take different amounts of your medicines or to take different medicines while you are having Dihydergot.

Use in pregnancy (Category C)

Do not have Dihydergot if you are pregnant or intend to become pregnant. This medicine may affect your developing baby if you have it while you are pregnant.

Use in breastfeeding

The active ingredient in Dihydergot may pass into breast milk and may affect your baby. However, one or two doses are unlikely to be of concern. You should check with your doctor if Dihydergot is indicated while you are breastfeeding.

Schedule

S4

Common side effects

All medicines can have side effects. Common side effects are those which occur in more than 1% patients given Dihydergot:

• nausea and vomiting
• abdominal pain
• muscle pain
• weakness
• diarrhoea
• headache
• numbness and tingling
• cold extremities
• dizziness
• fast, slow or irregular heart beat
• shaking or tremor
• feeling anxious or restless
• dry mouth
• flushing of the skin

Do not be alarmed by the possible side effects listed. The are usually mild and you may not even experience any of them. However, do not hesitate to see your doctor if they worry you.

Uncommon side effects

Do not be alarmed by the list of side effects below. They are generally uncommon (less than 1%) and you may not experience any of them. However, if you feel unwell after taking Dihydergot or notice any of the following symptoms, you should tell your doctor immediately.

• signs of allergy such as rash, itching or hives on the skin, swelling of the face, lips, tongue or other part of the body, wheezing or troubled breathing
• signs of “ergotism” (excessive constriction of blood vessels) such as numbness, coldness, tingling or a pale or bluish colour in the fingers or toes, pain or spasms in muscles, weakness in the lower legs, chest pain
• pain in the lower back or side, associated with difficulty in passing urine or pain on urinating, which may be a sign of a thickening of the abdominal lining that can cause obstruction of the urinary tract
• shortness of breath, dry cough, pain in the chest or rib area
• seizures

References

1. Australian Medicines Handbook. Dihydergot. January 2008 [cited 2008 June 22]. Available from: [URL Link]
2. MIMS Online. Dihydergot. 11 June 2003 [cited 2008 June 22]. Available from: [URL Link]

For further information talk to your doctor.