Benzodiazepines 4- Antihistamines

Opioid analgesics Tricyclic antidepressants Sedating antihistamines Benzodiazepines and other hypnotics Barbiturates... 

Toxicity Nausea, diarrhea, thrombocytopenia, hyperbilirubinemia, and nephrolithiasis occur. To reduce renal damage, it is important to maintain good hydration. Indinavir is a substrate for and an inhibitor of the cytochrome P450 isoform CYP3A4 and is implicated in drug interactions. Serum levels of indinavir are increased by azole antifungals and decreased by rifamycins. Indinavir increases the serum levels of antihistamines, benzodiazepines, and rifampin. 

Drug interactions other narcotics, antihistamines, benzodiazepines, antipsychotics, antianxiety agents, or other CNS depressants. Use of MAO inhibitors or tricyclic antidepressants can increase the effect of hydrocodone. It is not recommended for pediatric use Pregnancy Category C [1,2,8]. 

Medications for symptomatic relief from vertigo consist of antiemetics, benzodiazepines and antihistamines. They are all mostly aimed at the psychological consequences of dizziness and can all have highly unfavourable side effects, for example, sedation, anticholinergic effects and insomnia. The psychological consequences of dizziness in elderly should rather be treated with information about the condition, supportive help actions and increased social activities, than with drugs. 

Antihistamines. Some clinicians have prescribed the antihistamine, hydroxyzine (Vistaril, Atarax) to treat anxiety. A typical regimen is 25 mg administered one to three times per day as needed for anxiety. The use of hydroxyzine to treat anxiety is largely driven by concern regarding the addictive potential of benzodiazepines. In reality, hydroxyzine does little to relieve anxiety other than produce drowsiness. Because other nonaddictive anxiolytics are available, we do not recommend routine use of this largely ineffective treatment. 

Phenergan contains the antihistamine promethazine. Valium contains the benzodiazepine diazepam. Both the antihistamine and the benzodiazepine tend to reduce the blink rate, leading to dry eyes. Cilest is a combined oral contraceptive, which, like other oral contraceptives, may cause reduced tolerance because of corneal and eyelid oedema. 

Hypnotics fall into different categories, including the benzodiazepines (e.g., triazolam, temazepam, clotiaze-pam, nitrazepam), barbiturates (e.g., hexobarbital, pentobarbital), chloral hydrate, and Hi-antihistamines with sedative activity (p. 114). Benzodiazepines act at specific receptors (p. 226). The site and mechanism of action of barbiturates, antihistamines, and chloral hydrate are incompletely understood. 

Drugs that may be affected by SSRIs Drugs that may be affected by SSRIs include alcohol, benzodiazepines, beta blockers, buspirone, carbamazepine, cisapride, clozapine, cyclosporine, diltiazem, digoxin, haloperidol, hydantoins, lithium, methadone, mexiletine, nonsedating antihistamines, NSAIDs, olanzapine, phenothiazines, phenytoin, pimozide, procyclidine, ritonavir, ropivacaine, sumatriptan, sulfonylureas, sympathomimetics, tacrine, theophylline, tolbutamide, tricyclic antidepressants, and warfarin. 

Drugs that may affect nelfinavir include anticonvulsants, azithromycin, azole antifungals, efavirenz, delavirdine, HMG-CoA reductase inhibitors, indinavir, interleukins, nevirapine, rifabutin, rifampin, ritonavir, saquinavir, St. John s wort. Drugs that may be affected by nelfinavir include amiodarone, antiarrhythmics (amiodarone, quinidine), azithromycin, benzodiazepines, efavirenz, ergot alkaloids, delavirdine, didanosine, fentanyl, indinavir, lamivudine methadone, nonsedating antihistamines, oral contraceptives, phenytoin, pimozide, quinidine, rifabutin, saquinavir, sildenafil, sirolimus, tacrolimus, zidovudine. 

Diazepam (Valium, Diastat) [C-IVj [Anxiolytic, Skeletal Muscle Relaxant, Anticonvulsant, Sedative/Hypnotic/ Benzodiazepine] Uses Anxiety, EtOH withdrawal, muscle spasm, status epilepticus, panic disorders, amnesia, preprocedure sedation Action Benzodiazepine Dose Adults. Status epilepticus 5-10 mg IV/IM Anxiety 2-5 mg IM/IV Preprocedure 5-10 mg IV just prior to procedure Peds. Status epilepticus 0.5-2 mg IV/IM Sedation 0.2-0.5 mg/kg IV (onset w/in 5IV and 30 min IM duration about 1 h IV and IM) Caution [D, / -] Contra Coma, CNS depression, resp d es-sion, NAG, severe uncontrolled pain, PRG Disp Tabs 2, 5, 10 mg soln 1, 5 mg/mL inj 5 mg/mL rectal gel 2.5, 5, 10, 20 mg/mL SE Sedation, amnesia, bradycardia, i BP, rash, X resp rate Interactions T Effects W/ antihistamines, azole antifungals, BBs, CNS depressants, cimetidine, ciprofloxin, disulfiram, INH, OCP, omeprazole, phenytoin, valproic acid, verapamil, EtOH, kava kava, valman T effects OF digoxin, diuretics X effects w/ barbiturates, carbamazepine. 

Flurazepam (Dalmane) [C-IV] [Sedative/Hypnotic/ Benzodiazepine] Uses Insomnia Action Benzodiazepine Dose Adults Beds >15 y. 15-30 mg PO qhs PRN X in elderly Caution [X, /-] Elderly, low albumin, hepatic impair Contra NAG PRG Disp Caps SE Hangover d/t accumulation of metabolites, apnea, anaphylaxis, angioedema, amnesia Interactions T CNS depression W/ antidepressants, antihistamines, opioids, EtOH T effects OF digoxin, phenytoin T effects W/ cimetidine, disulfiram, fluoxetine, iso-niazid, ketoconazole, metoprolol, OCPs, propranolol, SSRIs, valproic acid. 

Quazepam (Doral) [C IV] [Sedative/Hypnotic/ Benzodiazepine] Uses Insomnia Action Benzodiazepine Dose 7.5-15 mg PO hs PRN i in elderly hqjatic failure Caution [X, /-] NA glaucoma Contra PRG, sleep apnea Disp Tabs SE Sedation, hangovCT, somnolence, resp depression Interactions T Effects W/ azole antifungals, cimetidine, digoxin, disulfiram, INH, levodopa, macrolides, neuroleptics, phenytoin, quinolones, SSRIs, verapamil, grapefruit juice, EtOH effects W/carbamazepine, rifampin, rifabutin, tobacco EMS Use caution w/ other benzodiazepines, antihistamines, opioids and verapamil, can T CNS depression concurrent EtOH and grapefruit juice use T CNS depression OD May cause profound CNS depression, confusion, bradycardia, hypotension, and altered reflexes flumazenil can be used as antidote activated charcoal may be effective... 

In the treatment of children and adolescents with anxiety disorders clinicians have a wide variety of pharmacologic options beyond the antidepressants (Shader and Greenblatt, 1995 Lydiard et ah, 1996 Riddle et ah, 1999). The benzodiazepines (BZs), with their favorable safety profile and quick onset of action, are attractive alternatives for the treatment of acute anxiety. While the clinical effectiveness of buspirone has not been proven in children, buspirone is used alone or in combination with other drugs in the treatment of anxiety disorders. The antihistamines are often used to treat insomnia and may reduce acute mild agitation. Zolpidem (Ambien) is occasionally used for its sedative properties. This chapter reviews the structure, proposed mechanisms of action, pharmacodynamic principles, and pharmacokinetic principles of these drugs. 

For those with a history of substance abuse or intolerance to benzodiazepines and the elderly, caution must be used in controlling anxiety. In these cases, benzodiazepines may exacerbate other conditions. Preliminary reports suggest that antipsychotics such as quetiapine may alleviate symptoms of anxiety. Other strategies include use of antihistamines such as hydroxyzine and diphenhydramine. 

The tranquillizers like benzodiazepines (diazepam 5-10 mg oral, or lorazepam 2 to 4 mg IM, IV are now preferred for preanaesthetic medication because they produce tranquillity, have better muscle relaxant property and smoothen induction. Other tranquillizer compounds include phenothiazines which possess sedative, antiemetic and antihistaminic properties. They can be given orally as well as parenterally. 

These medications are only safe to use with other substances under a physician s supervision. Typically, they should not be used with alcohol, antihistamines, barbiturates, or benzodiazepines. Because these other substances slow breathing, their effects in combination with opioids could lead to life-threatening respiratory depression. 

So how is insomnia treated Most commonly, people self-medicate their insomnia with over-the-counter medications such as Tylenol PM , Sominex , Unisom , or other drugs such as antihistamines (discussed in Chapter 3). Other people try natural remedies such as melatonin (see Chapter 4). When such medications don t work, people often ask their doctor for a prescription sleep aid, which is usually a type of medication called a benzodiazepine such as Halcion or a related type of drug such as Ambien or Sonata (see Chapter 6 for more on these types of drugs). 

The quinazolone methaqualone (129 R = Me) was introduced as a sedative in 1965. It also has anticonvulsant and muscle-relaxant properties, but it has produced problems of addiction. Sedative effects are also produced by many antihistamines, and by tranquilizers of the benzodiazepine group. 

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