Overview
Inversine is the brand name for Mecamylamine, an antihypertensive. Antihypertensives are usually used to treat high blood pressure. Inversine lowers blood pressure by relaxing the muscles around blood vessels.

The FDA recently approved the use of Inversine for patients with Tourette Syndrome (TS). It is believed to cause many of the same calming effects on such as facial tics as nicotine, and even binds to the same receptors in the brain. Inversine is also known as a nicotine antagonist (nicotine blocker) because it inhibits nicotine binding to its receptors by competing with it for these receptors. In other words, Inversine may produce many of the same calming effects of nicotine without most of the side effects that accompany nicotine in any form.

Inversine’s effect in other disorders such as attention-deficit hyperactivity disorder (ADHD), essential tremor, obsessive-compulsive disorder (OCD), bipolar disorder (manic-depressive illness), and chronic fatigue syndrome is still being studied.

Why is this drug prescribed?
Inversine is used to treat Tourette Syndrome (TS). It appears to improve a broad range of symptoms including motor and vocal tics, irritability, aggression, tension, and mood. Inversine is often used in combination with other drugs to treat Tourette syndrome. When Inversine is used along with another medication, it may lower the amount of the first medication needed to control symptoms and thus reduce the risk of side effects associated with that medication. When Inversine is used to treat Tourette Syndrome, it is used in a much lower dose (about 2 to 5 mg per day) than that used to treat hypertension (about 5 to 75 mg per day).

Inversine is also (and more traditionally) used to treat high blood pressure but is rarely used for this purpose any longer.

Warnings
Studies of Inversine’s effects on Tourette Syndrome have included children at least as young as 8 years old. Further studies in children are still being conducted.

Because it lowers blood pressure, Inversine may cause dizziness or faintness. Patients should use caution when operating a motor vehicle or heavy machinery.

For Pregnant or Nursing Mothers: There have not yet been any studies of Inversine in pregnant or nursing mothers. Antihypertensive medications are generally not recommended for pregnant women because pregnant women are generally more sensitive to their effects. Also, Inversine may cause bowel problems in the unborn baby.

Contraindications
Inversine should Not be used for people with the following medical conditions:

1. Pyelonephritis (kidney infection and inflammation) – patients being treated for chronic pyelonephritis with sulfonamides or antibiotics should not take Inversine.

Precautions
Inversine may be used with caution in patients with the following conditions:

1. bladder or prostate problems - Inversine may interfere with urination and aggravate these conditions.
2. bowel problems – this increases the risk of Inversine causing serious bowel side effects.
3. diarrhea, fever, infection, vomiting – such conditions increase the risk of dehydration and may lead to a more drastic change in blood pressure.
4. Glaucoma – Inversine may worsen this condition.
5. Heart or blood vessel disease or a recent heart attack or stroke – Inversine may worsen these conditions
6. Kidney disease – Inversine’s effects may be increased because it is eliminated more slowly from the body.

Adverse Reactions
Inversine may cause the following reactions:

1. dizziness / lightheadedness
2. drowsiness or tiredness
3. fainting
4. dry mouth, nose, or throat
5. difficulty urinating
6. Blurred vision
7. Decreased libido
8. Enlarged pupils
9. loss of appetite
10. nausea and vomiting
11. weakness
12. bloating
13. loose stools
14. confusion or excitement
15. constipation
16. convulsions / seizures
17. depression
18. shortness of breath
19. trembling
20. uncontrolled movements of face, hands, arms, or legs

Interactions with Drugs and Other Substances
Drugs or substances that may interact with Inversine include:

1. sulfonamides (sulfa medicine) – patients being treated for chronic pyelonephritis with sulfonamides should not take Inversine.
2. Urinary alkalizers (medicines that makes the urine less acidic) including acetazolamide (Diamox), antacids that contain calcium or magnesium, dichlorphenamide (Daranide), methazolamide (Neptazane), sodium bicarbonate (baking soda) potassium or sodium citrate and/or citric acid (found in citrus fruits and some artificial flavorings) – these medications may increase Inversine's effects and slow the rate at which it is eliminated from the body.
3. Antimyasthenics such as ambenonium (Mytelase), neostigmine (Prostigmin), and pyridostigmine (Mestinon) – Inversine may lower the effectiveness of these medications.
4. Over the counter medications for appetite control, asthma, colds, cough, hay fever, or sinus problems – such medications may counteract the effects of Inversine.

Sources

http://www.healthtouch.com/bin/EContent_HT/drugShowLfts.asp?
fname=usp0151.htm&title=Inversine&cid=HTDRUG

http://www.laytonbio.com/inversine/treatment_of_tourette-article.htm

http://www.pslgroup.com/dg/1d1b82.htm

http://www.tourette-syndrome.com/_disc1/00000162.htm