BMA Concise Guide to Medicine & Drugs

Rivastigmine

Brand name Exelon

Used in the following combined preparations None

QUICK REFERENCE

Drug group Drug for dementia

Overdose danger rating Medium

Dependence rating Low

Prescription needed Yes

Available as generic Yes

GENERAL INFORMATION

Rivastigmine is an inhibitor of the enzyme anticholinesterase. This enzyme breaks down the naturally occurring neurotransmitter acetylcholine to limit its effects. Blocking the enzyme raises the levels of acetylcholine which, in the brain, increases alertness, awareness, and memory. Rivastigmine has been found to improve the symptoms of dementia in Alzheimer’s disease, and is used to slow the rate of deterioration in that disease. The drug is not recommended for dementia due to other causes. Treatment with rivastigmine is initiated under specialist supervision. It is usual to assess those being treated at six monthly intervals to decide whether the drug is helping. As the disease progresses, the benefit obtained may diminish.

Side effects may include agitation, confusion and depression, which could be thought due to Alzheimer’s disease. Weight loss should be monitored.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Capsules, liquid.

Frequency and timing of doses 2 x daily.

Adult dosage range 3mg daily (starting dose); 6–12mg daily (maintenance dose).

Onset of effect 30–60 minutes. Full effect may take up to 3 months.

Duration of action 9–12 hours.

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children.

Missed dose Take as soon as you remember. If your next dose is due within 4 hours, take a single dose now and skip the next. A carer should be overseeing the taking of tablets.

Stopping the drug Do not stop the drug without consulting your doctor; symptoms may recur.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a problem. Large overdoses may cause nausea, vomiting, and diarrhoea. Notify your doctor.

POSSIBLE ADVERSE EFFECTS

Common adverse effects of rivastigmine include drowsiness, dizziness, weakness, trembling, sweating, and tiredness. Discuss with your doctor if these are severe. Reduced appetite, weight loss, nausea, abdominal pain, agitation, confusion, urinary incontinence, and infection are also common and should be notified to your doctor in all cases. Mental changes and intestinal problems, although common, are usually quite mild. Women may be more susceptible to nausea, vomiting, and weight loss. Rarely, seizures may occur; if so, stop taking the drug and contact your doctor immediately.

INTERACTIONS

Muscle relaxants used in surgery Rivastigmine may increase the effects of some muscle relaxants, but it may also block the effects of some others.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have a heart problem.

· You have liver or kidney problems.

· You have asthma or respiratory problems.

· You have a history of peptic ulcers.

· You have had an epileptic seizure.

· You are taking other medicines.

Pregnancy Not recommended. Safety in pregnancy not established.

Breast-feeding Not recommended.

Infants and children Not recommended.

Over 60 No special problems.

Driving and hazardous work Your underlying condition may make such activities inadvisable. Discuss with your doctor.

Alcohol Avoid. Alcohol increases the sedative effects of rivastigmine.

Surgery and general anaesthetics Treatment with rivastigmine may need to be stopped before you have a general anaesthetic. Discuss this with your doctor or dentist before any operation.

PROLONGED USE

May be continued for as long as there is benefit. Stopping the drug leads to a gradual loss of the improvements.

Monitoring Checks at 6-monthly intervals may be performed to test whether the drug is still providing some benefit.