COCAINE HYDROCHLORIDE Solution Ref.[9265] Active ingredients: Cocaine

Indications from some studies of medicinal cocaine show that death can ensue from 0.8-1.0g (8-10ml of a 10% w/v solution of cocaine).

Some persons have a cocaine idiosyncrasy and death may occur quite suddenly after doses of only 20mg.

Cocaine should not be applied to damaged mucosa or open wounds because of the risk of systemic toxicity from enhanced absorption.

Cocaine should be used with caution in patients with hypertension, cardiovascular disease or thyrotoxicosis because the vasoconstriction and tachycardia may reduce cardiac oxygenation while increasing oxygen demand It should also be used with caution in patients with diabetes because cocaine sensitises the person to adrenaline which mobilises glucose and causes blood glucose levels to go out of control.

At high doses cocaine depresses the respiratory centres and thus should be cautiously employed in combination with other respiratory depressants (e.g. opiates, barbiturates, alcohol).

The use of cocaine in the elderly is not recommended because of the risk of vasoconstriction and tachycardia. Cocaine is also not recommended in children, or in pregnancy or lactation.

Overall, the patient’s condition, the appropriate dose and method of administration must all be considered prior to the application of cocaine. The initial signs and symptoms of cocaine toxicity and the appropriate treatment required to combat toxicity must be known to the surgeon or anaesthetist.

Cholinesterase Inhibitors.

e.g. Ecothiopate eye drops for the treatment of Glaucoma, and neostigmine for the treatment of Myasthenia Gravis.

If these drugs are administered to patients receiving cocaine, higher blood levels result, with a greater risk of drug toxicity. (See Contra-indications)

Adrenaline and other sympathomimetics.

Adrenaline is believed to enhance the toxic effects of cocaine by further increasing the level of circulating catecholamines. (See Contra-indications)

Ephedrine is used in the treatment of reversible airways obstruction and is present in some cough linctus preparations. Amphetamines (CNS stimulants) have some similar actions to sympathomimetics..

Monoamine-Oxidase Inhibitors.

Cocaine potentiates the effects and toxicity of MAO inhibitors, e.g. phenelzine or isocarboxazid.

α-Modifying Drugs.

e.g. guanethidine sulphate and reserpine, both used in the treatment of hypertension; and tricyclic anti-depressants such as imipramine and amitriptyline. These drugs also increase the activity of the Sympathetic Nervous System, which is also increased by administration of cocaine.

Halothane.

Maintenance of anaesthesia with halothane, a volatile anaesthetic agent, may augment any interaction between cocaine and catecholamines by sensitising the myocardium. However, deeper levels of general anaesthesia inhibit adrenal release of catecholamines and may conversely decrease the potential arrhythmogenic effects.

Cholinesterase Inhibitors.

Cocaine is not recommended for use during pregnancy and lactation.

Cocaine exposure early in pregnancy is reflected by cocaine and metabolite burden in the meconium, which is initially formed at the end of the first trimester, due to cocaine crossing the placenta.

Animal and autopsy studies indicate that the cocaine metabolite benzoylecgonine preferentially accumulates in foetal tissue. Recent human and animal studies suggest that the slowly eliminated metabolites of cocaine have significant physiological and behavioural properties. There is also an increased risk of spontaneous abortion and other birth complications due to vasoconstriction by cocaine increasing maternal blood pressure and reducing placental blood flow.

The following signs and symptoms are typical of babies born following cocaine use by the mother during pregnancy: irritability, inconsolability, hypertoxicity, tremulousness, hyperactive moro reflex, sneezing or yawning, lethargy, suck reflex, high pitched cry, poor feeding, poor weight gain, fever, diarrhoea, spitting or vomiting, tachypnoea, tachycardia, skin abrasions and respiratory distress. Cocaine is also excreted in breast milk.

Due to the pharmacological actions of cocaine, it is recommended that patients who have been administered cocaine do not drive or operate machinery.

This medicine can impair cognitive function and can affect a patient’s ability to drive safely. This class of medicine is in the list of drugs included in regulations under 5a of the Road Traffic Act 1988. When prescribing this medicine, patients should be told:

• The medicine is likely to affect your ability to drive
• Do not drive until you know how the medicine affects you
• It is an offence to drive while under the influence of this medicine
• However, you would not be committing an offence (called ‘statutory defence’) if:
  • The medicine has been prescribed to treat a medical or dental problem and
  • You have taken it according to the instructions given by the prescriber and in the information provided with the medicine and
  • It was not affecting your ability to drive safely.

Cocaine may cause restlessness, excitement, euphoria, garrulousness and increased motor activity. With high doses or repeated use, confusion, paranoia, hallucinations, altered tactile sensations and psychosis have been reported. Seizures can occur, perhaps due to lowering of the seizure threshold, or hyperpyrexia, or due to life threatening cardiac arrhythmias.

Cocaine directly causes a rise in body temperature by increasing heat production through stimulated muscle activity, and indirectly by causing vasoconstriction that decreases heat loss. A direct pyrogenic effect may be caused by cocaine’s direct effect on thermoregulatory centres in the hypothalamic area.

Low doses of cocaine in humans do not change respiratory rate or depth, but at higher doses a CNS mediated increase in respiratory rate and decrease in tidal volume is described.

A migraine-like headache may be the result of cocaine induced vascular changes. Adrenergic stimulation may cause intensive hypertension, due to tachycardia and peripheral vasoconstriction. Cocaine increases cardiac activity, which raises oxygen demand within myocardial tissue. Other signs of adrenergic excess seen with cocaine include mydriasis, diaphoresis, tremor, hyperactive bowel sounds and hyperreflexia. Vasoconstriction due to cocaine may also produce ischaemia in the fingers, toes, spinal cord, kidneys, spleen, and intestines.

Cocaine suppresses Rapid Eye Movement (REM) sleep and total sleep. In low doses cocaine has an anorexic effect.

Cocaine hydrochloride solution is incompatible with phenol, sodium borate and silver nitrate.