PubMed Health⌕ Search

Biomedical subjects

P Pritchard

Publications and source records attributed to P Pritchard.

At least 19 recordsLinked to original sources
PubMed1998

Induction of CYP1A2 activity by carbamazepine in children using the caffeine breath test.

AIMS: Carbamazepine is a known enzyme inducer. The aim of this study was to determine whether carbamazepine induces the metabolism of caffeine in children. METHODS: Children due to receive carbamazepine for epilepsy were recruited into the study. The caffeine breath test was carried out prior to the administration of carbamazepine and after a minimum of 2-3 weeks therapy. Five children were studied and they received 200-600 mg carbamazepine daily. RESULTS: The mean values of the 2 h cumulative labelled carbon dioxide were 3.47% before and 7.65% during carbamazepine. There was a significant increase in the percentage labelled caffeine exhaled as carbon dioxide during the administration of carbamazepine (Student's paired t-test, P < 0.05). CONCLUSIONS: The results suggest that carbamazepine induces the metabolism of caffeine by the CYP1A2 pathway in the children studied.

Adolescent↗
PubMed1997

Lack of inhibitory effect of cimetidine on caffeine metabolism in children using the caffeine breath test.

AIMS: To study the potential drug interaction between cimetidine and caffeine in a group of children who received cimetidine for gastritis. METHODS: The caffeine breath test was carried out prior to the administration of cimetidine and after 2-3 weeks therapy. The children (n = 1) received 300-800 mg cimetidine daily (11-36 mg kg(-1) day(-1)). RESULTS: There was no significant change in the 2 h cumulative labelled CO2 following the administration of cimetidine (mean values 5.61% before and 4.87% during cimetidine; Student's t-test P > 0.2). CONCLUSIONS: Cimetidine did not have an inhibitory effect on the metabolism of caffeine in this group of children studied.

Adolescent↗
PubMed1997

Enhanced drug metabolism in young children with cystic fibrosis.

The effect of cystic fibrosis on caffeine metabolism was studied in young children using the caffeine breath test. Eight children with cystic fibrosis aged 2-6 years and nine age matched controls were studied on a single occasion, and the cumulative percentage of labelled caffeine exhaled as carbon dioxide measured over two hours. This was significantly higher in the patients with cystic fibrosis than in controls, suggesting an increase in the CYP1A2 metabolic pathway in the former. The fact that these were young children with minimal lung and liver disease suggests that enhanced drug metabolism in children with cystic fibrosis is hereditary rather than secondary to lung and liver damage.

Breath Tests↗
PubMed1994

Behavioural work with pre-school children in the community.

As many as 25 per cent of pre-school children are regarded by their parents as having behaviour problems. Such problems can continue into the school-age years. Behaviour difficulties in a young child can have implications for the mother's health and for family relationships. Pam Pritchard evaluates a specialist health visiting initiative to tackle child behaviour disturbance.

Child Behavior Disorders↗
PubMed1993

Blockade of GABA receptors in superior colliculus protects against focally evoked limbic motor seizures.

Blockade of GABA receptors in the rat superior colliculus (SC) has been shown to protect against maximal electroshock-induced tonic convulsions and spontaneous generalized non-convulsive seizures. In the present study, we determined that blockade of GABA receptors in SC could also protect against focally evoked limbic motor seizures. Limbic motor seizures were induced by the unilateral focal application of bicuculline methiodide into area tempestas (AT), an epileptogenic site in the deep prepiriform cortex. Control rats (receiving bilateral infusions of saline into SC) all exhibited convulsive seizures following bicuculline in AT. Rats pretreated (5 min before) with bicuculline (50 pmol) bilaterally in the deep layers of the SC, were protected against the AT-evoked convulsive seizures. Unilateral application of bicuculline in the deep SC or bilateral application in the superficial layers of the SC did not alter the convulsive response to bicuculline in AT. These results indicate that the anticonvulsant action of GABA blockade in SC is not limited to tonic convulsive seizures but extends to the clonic manifestations evoked by seizures originating in forebrain limbic circuits. Given that the deep layers of SC receive inputs from GABA neurons in substantia nigra and that suppression of the activity of nigral neurons is anticonvulsant against a variety of seizures (including those evoked from AT), it is likely that the anticonvulsant action of bicuculline in SC is due to interference with the influence of a nigrotectal GABAergic projection.

Animals↗
PubMed1989

Managing the world outside the practice.

Health care depends on the esteem and co-operation of many people and organisations outside the ill-defined boundary of the practice. We need to build up networks of people working in a climate of co-operation, not competition or conflict. In this way we can achieve our goals in today's turbulent environment.

Cooperative Behavior↗
PubMed1984

Venous pressures during simulated Bier's block.

Venous pressures in the forearm veins during the simulated performance of intravenous regional analgesia were measured. Pressures obtained equalled or exceeded the recommended occluding pressure of the tourniquet. This finding is proposed as one of the possible reasons for the occasional observation that convulsions may occur during Bier's block despite the presence of an intact tourniquet system.

Anesthesia, Conduction↗