advertisement

Meds and you

27 September 2013

Phenobarbitone

Phenobarbitone is a barbiturate. Barbiturates are drugs that depress the central nervous system. They are frequently used to treat insomnia and seizures.

0

(Also known as Phenobarbital)

Phenobarbitone is the actve ingredient of Lethyl (Nappi Code: 737844-019).

Phenobarbitone is also one of the active ingredients found in Adco-Phenobarbitone Vitalet (Nappi Code: 754803-007) and Propain Forte (Nappi Code: 757667-007).

General information
Phenobarbitone is a barbiturate. Barbiturates are drugs that depress the central nervous system. They are frequently used to treat insomnia and seizures.

In South Africa phenobarbitone is registered for the treatment of epilepsy, anxiety and migraine. The arrival of newer sleeping drugs has brought along safer and more effective hypnotics - for this reason phenobarbitone is not indicated for short-term treatment of the inability to fall asleep or to remain asleep throughout the night.

Phenobarbitone can be habit-forming and should only be taken as directed by your doctor, and only for as long as recommended.

Phenobarbitone does not cure the underlying condition being treated, but simply keeps the symptoms under control.

Treatment with this drug should not be stopped abruptly, especially if you have been taking phenobarbitone for a prolonged period of time. To prevent withdrawal symptoms (including seizures) you should decrease your dose gradually, only as directed by your doctor.

Owing to phenobarbitone's many side-effects, other newer anticonvulsants are mostly preferred above this drug.

Phenobarbitone may cause a folic acid deficiency in the body and folic acid supplementation is advised.

How does phenobarbitone work?
Phenobarbital reduces over-activity of the central nervous system that may lead to a seizure.

Fast facts

Drug schedule: schedule 5
Available as: phenobarbitone is available as tablets and as a syrup.
What does it do? Phenobarbital depresses the central nervous system to keep seizures under control.
Overdose risk: high
Dependence risk: high
Is Phenobarbitone available as a generic? yes
Is Phenobarbitone available on prescription only? yes

User information

Onset of effect: within 1 hour
Duration of action: up to 12 hours
Stopping this medicine: treatment with this drug should not be stopped abruptly. To prevent withdrawal symptoms (including seizures) your dose should be gradually reduced by your doctor.
Prolonged use: prolonged use may lead to dependence and tolerance.

Special precautions
Consult your doctor before using this drug if:

  • you have porphyria

  • you have liver or kidney disease

  • you have diabetes

  • you have a thyroid disorder

  • you have asthma

  • you have a history of alcohol or substance abuse

Pregnancy: avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.
Breastfeeding: avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.
Porphyria: avoid. This medication may cause serious adverse effects. Consult your doctor before use.
Infants and children: a reduced dose is needed as this drug may increase the likelihood of adverse effects.
The elderly: caution is advised in the elderly as this drug may increase the likelihood of adverse effects.
Driving and hazardous work: this medication should be avoided as it may cause extreme sedation.
Alcohol: avoid concomitant use of alcohol with this medication.

Possible side effects

Side Effect
Frequency
Consult your doctor

Common
Rare
Only if severe
In all cases
drowsiness
X

X

dizziness

X
X

headache

X
X

nausea/vomiting

X
X

constipation

X
X

loss of balance

X

X
loss of coordination

X

X
sun sensitivity

X
X

skin rash

X

X
anxiety

X
X

nightmares

X
X

yellow tinge to skin/eyes

X

X
swelling

X

X

Interactions

propranolol, etc. lower beta-blocker effect
felodipine lowers felodipine efficacy
nimodipine lowers nimodipine efficacy
carbamazepine risk of carbamazepine toxicity
alcohol, benzodiazepines, sedatives, etc. enhanced CNS effects
corticosteroids reduced corticosteroid effect
digoxin reduced digoxin effect
griseofulvin reduced Griseofulvin effect
oral contraceptives that contain oestrogen possible pill failure

Disease interactions
Consult your doctor before using this drug if you have porphyria, liver or kidney disease, diabetes, a thyroid disorder or if you have asthma.

Overdose action
An overdose of this medication can be fatal. Seek immediate emergency medical attention.

Recommended dosage
Adults: oral: 60-180 mg daily in one to two divided doses

This material is not intended to substitute medical advice, but is for informational purposes only. Please consult a physician for specific treatment and recommendations.
 
 

Read Health24’s Comments Policy

Comment on this story
0 comments
Comments have been closed for this article.