Drugs for the doctor's bag

Summary
The doctor's bag should contain drugs to treat life-threatening emergencies and other serious medical conditions. Almost all of these emergency drugs are administered parenterally, but it is helpful to carry oral and inhaler preparations for certain conditions. Storage and safe-keeping should be considered in selecting appropriate drugs. The emergency drugs provided by the Pharmaceutical Benefits Scheme cover most situations.

Introduction
General practitioners visiting patients in the community require the traditional doctor's bag which should contain basic drugs for emergency use. These drugs should also be available for the inevitable emergencies which occur in the doctor's office.

Most of the drugs needed for emergency treatment are provided to medical practitioners by the Pharmaceutical Benefits Scheme (PBS). The drugs are listed in the Emergency Drug (Doctor's Bag) Supplies section of the Schedule of Pharmaceutical Benefits.

Deciding what to carry
The choice of drugs depends on several factors including the practice location, conditions likely to be met, the shelf-life and climatic vulnerability of the various drugs (e.g. antibiotics, vaccines), and the design and size of the bag.

The bag should contain drugs which are relatively safe and simple to use. More sophisticated drugs such as those used in cardiac emergencies are best reserved for hospital use where circumstances permit.

Drugs
Most of the drugs listed in Table 1 are injectable. Non-injectable drugs that should be carried are soluble aspirin, diazepam, glyceryl trinitrate (a sublingual spray is more stable than tablets) and salbutamol aerosol. Some practitioners would choose to carry other non-injectables such as indomethacin suppositories (for renal colic), oral sedatives or hypnotics, analgesics, antibiotics and antiemetics. The drugs in the bag should be checked regularly so that out-of-date drugs can be replaced.

Severe pain
If an opioid is given for severe pain, it should be used and recorded in accordance with Schedule 8 regulations.

Morphine sulphate 15 mg/mL
Morphine can be used for:

• acute pulmonary oedema
• relief of severe pain such as myocardial infarction (but not pain due to biliary or renal colic where morphine may increase pain by exacerbating smooth muscle spasm)

The usual dose for the above conditions is 5-10 mg by slow intravenous injection. This is usually combined with an injection of antiemetic such as metoclopramide (10 mg/2 mL) to reduce vomiting, a common adverse effect of morphine.

Pethidine 100 mg/2 mL
Pethidine can be used in a variety of severe, painful conditions, especially ureteric and biliary colic. Dependence is an issue, so pethidine should be avoided for frequently recurring conditions such as migraine.

Other analgesics
Indomethacin suppositories can supplement pethidine for renal colic. Paracetamol (500 mg tablets or 120 mg/5 mL paediatric oral suspension) is useful for mild to moderate pain.

Myocardial infarction

Aspirin
Aspirin 300 mg is first-line treatment for all patients suspected of having a myocardial infarction, unless aspirin is contraindicated (see 'Acute myocardial infarction' Aust Prescr 1996;19:52-4).

Glyceryl trinitrate spray or tablets
Give one dose buccally or sublingually at once, then every 5 minutes if necessary (maximum 2-3 doses). In some States, the spray has to be considered as a multi-dose vial i.e. it can only be used for one patient.

Morphine sulphate
Give 5-15 mg by slow intravenous injection titrated against the response. It is usually combined with 10 mg metoclopramide given intravenously as an antiemetic.

Thrombolytics and anticoagulants
Streptokinase and heparin are best deferred until the patient is in hospital.

Arrhythmias
The management of arrhythmias outside hospital without monitoring is controversial. However, the Emergency Drug Supplies are quite generous with atropine, lignocaine and verapamil being available. Digoxin used for atrial fibrillation and atrial flutter is not available as a 'Doctor's Bag' item and this decision is in keeping with the recommendation that it should be used only in a hospital setting.

Atropine (600 microgram/mL)
A dose of 300-600 micrograms can be given intravenously for symptomatic bradycardia.

Lignocaine (100 mg/5 mL)
For ventricular tachycardia, 50-100 mg can be given intravenously over 5 minutes followed by an infusion.

Verapamil (5 mg/2 mL)
The intravenous dose of verapamil for patients with paroxysmal supraventricular tachycardia is 5 mg injected slowly. Verapamil is contraindicated if the patient is taking a beta blocker. It should be avoided in the acute stage of a myocardial infarction. In view of its potential adverse effects, which include heart block and asystole, perhaps verapamil should be replaced by adenosine in the doctor's bag. Adenosine has a half-life of less than 10 seconds so adverse effects generally disappear quickly.

Acute left heart failure (acute pulmonary oedema)
Patients with severe heart failure will need to be admitted to hospital. Before admission, treatment may include:

• frusemide (20 mg/2 mL injection) 20 mg intravenously
• (at maximum rate of 4 mg/minute), increasing to 80 mg if necessary
• morphine 5-10 mg intravenously slowly plus metoclopramide 10mg intravenously
• glyceryl trinitrate spray or tablet, repeated according to clinical response

Migraine
Most cases respond to simple analgesics, but moderate to severe cases may require parenteral treatment. The options are:

• metoclopramide (10 mg/2 mL) 10 mg intravenously plus oral analgesics
• metoclopramide 10mg intravenously plus dihydroergotamine mesylate which is approved for intramuscular or subcutaneous use for migraine
• (1 mg/mL) and for slow intravenous injection for cluster headache (0.5mg/0.5mL)
• sumatriptan 6 mg subcutaneously (not available on the PBS)
• pethidine by intramuscular injection may be effective for intense migraine, but it is best avoided if possible because of its addictive potential in the setting of a recurrent pain syndrome

Opioid respiratory depression
The number of patients presenting with the adverse effects of opioids, especially street drugs, is increasing.

Naloxone hydrochloride (2 mg/5 mL)
This is an essential component of the doctor's bag. The dosage is 2 mg intravenously or intramuscularly, repeated at 2-3 minute intervals to a maximum of 10mg. The patient should be carefully observed in case the respiratory depression recurs.

Opioid withdrawal
The need for any treatment is determined by the symptoms and their severity. Autonomic signs can be treated with oral clonidine, and diazepam can be used for anxiety and agitation.

Hypoglycaemia
In the PBS emergency drugs, only glucagon is listed. Glucagon (1mg/mL) may be given subcutaneously, intramuscularly or intravenously. While this may relieve most instances of hypoglycaemic coma, 50% glucose intravenously gives more rapid relief. Extravasation should be avoided. Intravenous glucose should be available as a 'Doctor's Bag' item.

Acute allergic reactions

Anaphylaxis
The first-line treatment is adrenaline.¹ The adult dose is 0.3-0.5 mg (1:1000) subcutaneously or intramuscularly. If there is no rapid improvement, the same dose is given intravenously over 2-5 minutes. Additional measures include:

• intravenous fluids
• salbutamol aerosol inhalation or nebulisation if severe
• promethazine (50 mg/2 mL solution) 0.5-1 mg/kg intravenously slowly

If still not responding, give adrenaline every 5 minutes and hydrocortisone 2-6 mg/kg intravenously.

Angio-oedema and acute urticaria
Give promethazine 25 mg intramuscularly. Add adrenaline 0.3mg subcutaneously if there is respiratory involvement.

Asthma
Injectable terbutaline, aminophylline and single-dose units of salbutamol nebuliser solution are available as 'Doctor's Bag' supplies. The first-line treatment for asthma is a nebulised B₂ agonist.² Use either salbutamol (1 mg/mL solution) 2.5-5 mg or terbutaline (2.5 mg/mL solution) 2.5-5 mg every 20 minutes. Ipratropium bromide (250 microgram/mL solution) 250-500 micrograms can be added to the nebuliser.

Hydrocortisone in both adults (200 mg intravenously, 6 hourly) and children (4 mg/kg intravenously, 6 hourly) is recommended for severe attacks. For less severe cases, oral corticosteroids may suffice.

If the response is poor, add salbutamol (500 microgram/mL) by slow bolus intravenous injection (5-10 microgram/kg up to 250 micrograms) then infusion. An alternative is aminophylline (250 mg/10 mL) by slow infusion if the patient has not received theophylline in the previous week.

For anaphylaxis or imminent cardiorespiratory arrest, give adrenaline 0.5 mg (adult) or 0.3 mg (children) intravenously or transtracheally.

Bleeding
For uterine bleeding, e.g. incomplete abortion, give ergometrine (250 microgram/mL) 1 mL intramuscularly.

Convulsions (generalised status)

Diazepam (10 mg/2 mL)
Give 5-20 mg intravenously (rate not exceeding 2 mg/minute). Diazepam can be given rectally by diluting 10 mg in 5 mL of isotonic saline and introducing it via the nozzle of the syringe into the rectum (10-20 mg in adults; 0.4 mg/kg in children). Rectal diazepam kits are available in some countries, but not Australia.

Intravenous phenytoin (100 mg/2 mL) is added (250-1000 mg) over 20-30 minutes if the attack is severe.

Infections
Benzylpenicillin, procaine penicillin and erythromycin are listed as 'Doctor's Bag' items. However, a case could be made for not carrying any of these drugs with perhaps the exception of benzylpenicillin.

Benzylpenicillin (600 mg vial)
Patients with suspected meningococcaemia should immediately be given an intravenous dose of 60 mg/kg (up to 4 g) (preferably after blood is taken for culture, although this is rarely practical and must not delay treatment). For adults with moderately severe pneumonia requiring parenteral therapy, give 600 mg intravenously.

Vaccines
The vaccines diphtheria/tetanus (2 types) and tetanus should not be carried in the bag, but stored in the refrigerator or cool space at the office (as for the antibiotics).

Psychiatric emergencies

Diazepam
The tablets and injection (10 mg/2 mL) have a variety of recommended uses, namely³:

• acute anxiety and panic disorder: 5 mg orally twice daily or 5 mg intravenously
• delirium with anxiety and agitation: 5 mg orally twice daily or 5 mg intravenously
• the acutely disturbed or agitated patient: 10-20 mg orally or 5-20 mg intravenously
• agitated schizophrenia and acute mania (to supplement haloperidol or droperidol): 10-20 mg orally or 5-10 mg intravenously

It would be appropriate to carry diazepam, but only the injection is available as a 'Doctor's Bag' item.

Haloperidol (5 mg/mL)
This is preferable to chlorpromazine (50 mg/2 mL) for acute psychotic emergencies in unco-operative patients. It is the favoured initial drug for psychotic delirium (5-10 mg intramuscularly), for acute schizophrenia (5-10 mg intravenously or intramuscularly) and acute mania (5-10 mg intravenously or intramuscularly).³

Benztropine mesylate (2 mg/2 mL)
A dose of 1-2 mg intravenously or intramuscularly is used for movement disorders from antipsychotic medication.

Vomiting
Several drugs are available as 'Doctor's Bag' supplies. Care should be taken with injections of these drugs in children who are susceptible to the extra pyramidal adverse effects of antiemetic drugs.

Metoclopramide (10 mg/2 mL)
This is suitable for most causes of vomiting, especially alimentary causes. Give 10 mg intravenously or intramuscularly over 1-2 minutes.

Prochlorperazine (12.5 mg/mL)
This is preferred for labyrinthine causes of vomiting such as Meniere's disease.

Haloperidol (5 mg/mL)
In patients with malignant disease, 1-2 mg intramuscularly can be given, especially if vomiting is due to morphine.

Diazepam (10 mg/2 mL)
A dose of 5 mg intravenously is effective for Meniere's disease.

Conclusion
While the form of the doctor's bag will vary from practice to practice, the drugs inside will be similar. The bag should be lockable and stored securely in a controlled environment when possible.

Further reading

Cooper CW, Hays RB. Emergencies in general practice [see comments]. Med J Aust 1992;156:541, 544-8. Comments in: Med J Aust 1992;157:143-4.

Murtagh J. General practice. Sydney: McGraw Hill 1994;1035-9.

Commonwealth Department of Health and Family Services. Schedule of pharmaceutical benefits. Canberra: Australian Government Publishing Service, August 1996.

Victorian Drug Usage Advisory Committee. Analgesic guidelines. 2nd ed. Melbourne: Victorian Medical Postgraduate Foundation, 1992.