Drug Interaction:
Interacting drugs - summary
Amphetamines +
Guanethidine
decrease antihypertensive effect of Guanethidine
MAO inhibitors
incr increase pressor response to amphetamine
Tricyclic antidepressants
decrease effects of amphetamine, increased dose may be necessary
Urinary acidifier
increase half-life and prolong activity of Amphetamine, a higher dose may bee necessary
Urinary alkaliniser
increase half-life and prolong activity of Amphetamine, a lower dose may be necessary.
Effect of drug on Lab test:
Plasma corticosteroid levels may be increased. The increase is greatest in the evening. Urinary steroid determinations may be altered by amphetamines.
Indication:
Narcolepsy,stabilising effect on children with a behavioural syndrome,
short term adjunct in weight reduction.
Adverse Reaction:
Palpitations,tachycardia,elevation of blood pressure,
reflex decrease in heart rate,arrhythmias (at large dose).
Overstimulation,restlessness,
Dizziness,insomnia,dyskinesia, euphoria, dysphoria,
tremor, headache, changes in libido.
Dry mouth,unpleasant taste, diarrhoea, constipation.
Anorexia may occur as undesirable effects when amphetamines are used other than anorectic effect .
Reversible elevations in serum thyroxine levels have occurred with heavy amphetamine use.
Urticaria,impotence.
Contra-Indications:
Advanced arteriosclerosis,
symptomatic cardiovascular disease moderate to severe hypertension, hyperthyroidism,
hypersensitivity to idiosyncrasy to sympathomimetic amines,
Glaucoma, agitated states,
history of drug abuse during or within 14 days following admin of MAO inhibitors(hypertensive crises may result).
Special precautions:
Hypertension-use cautiously- prescribe or dispense least amount feasible to minimise the possibility of overdosage.
May cause dizziness. Observe caution while driving or performing tasks requiring alertness.
Dosages/ Overdosage Etc:
Indications:
Narcolepsy,stabilising effect on children with a behavioural syndrome, short term adjunct in weight reduction.
Dosage:
Narcolepsy- 5 to 60mg/day in divided doses.
Children under 12 years- initial dose 5mg daily increment of 5mg at weekly intervals until a maximum of 60mg/day.
Adults - start with 10mg daily,raise with increments of 10mg/day at weekly intervals. If adverse reactions appear reduce dose.
Patient Information:
1. Take early in the day(especially sustained release dosage forms) to avoid nightmares.
2.Do not chew or crush sustained release. or long acting tablets.
3. Do not increase dosage except on advise of physician.
4.May impair ability to drive or perform tasks requiring alertness.
5. May cause nervousness,restlessness,insomnia,dizziness,anorexia, dry mouth and GI disturbances. Notify physician if these occur.
6.Allergies- Tell your doctor if you have had any allergic reactions to amphetamines, ehedrine, epinephrine, isoproterenol, norephinephrine.
7. Pregnancy- Animal studies have shown that amphetamines increase the chance of birth defects if taken during the months of pregnancy.
8. Breast feeding- amphetamines may pass into breast milk. It is best not to breast-feed while you are taking amphetamine.
9. Children- when amphetamines are used for long periods of time in children they may cause unwanted effects on behaviour and growth.
10. Elderly- no specific information compring use of amphetamine in the elderly with use in other age groups.
11. Other medicines- when you taking amphetamines, it is important for your doctor to know if you are taking any other medicines-
Amantadine Caffeine Chlophedianol Methylphennidate Nabilone Pemoline Appetite suppressants Medicines for asthma Medicines for cold, sinus problems or hay fever Beta-adrenergic blockers Cocaine Digitalis glycosides Meperidine MAO inhibitors Thyroid hormones Tricyclic antideprssants
12. Other medical problems- Make sure you tell your doctor if you have any other medical problems.
Anxiety or tension or Drug abuse or drug dependence or Glaucoma or Heart or blood vessel disease or High blood pressure or Overactive thyroid or Touretes syndrome- Amphetramine may make the condition worse.
Pharmacology/ Pharmacokinetics:
Pharmacology:
Amphetamines are sympathomimetic amines with CNS stimulant activity. CNS effects are mediated by release of norepinephrine from central noradrenergic neurons.
Pharmacokinetics:
Amphetamines are completely absorbed within 3 hours. Amphetamines are metabolised in the liver by aromatic hydroxylation.
Interaction with Food:
Reports not available.
Pregnancy and lactation:
Pregnancy:
Safety for use during pregnancy not established. Use only when needed.
Lactation:
Amphetamines are excreted in breast milk. Advise patients to discontinue nursing while taking amphetamines.
Children:
Do not use anorectic agents under 12 years of age.
Manufacturer Details