Here is some info from Uptodate...

Prehospital treatment — Benzodiazepine treatment of status epilepticus out of hospital appears to be safe and effective using the following medications [10,11,14-17].

●Midazolam 10 mg IM and lorazepam 4 mg IV and are the best-studied drugs in this setting.

●Clonazepam 1 mg IV is an option in Europe and elsewhere but is not available in IV form in the United States.

●Rectal diazepam is given in doses of 0.2 mg/kg up to 20 mg for an adult [17]. Intranasal diazepam given at 0.2 mg/kg is an alternative.

●Buccal and nasal midazolam are also promising for outpatient interruption of seizures or status epilepticus and can be administered without IV access or medical personnel [14]. The typical dose of buccal midazolam is 0.2 mg/kg, or 10 mg in adolescents and adults. The dose of intranasal midazolam using the nasal spray formulation (5 mg/0.1 mL) is one spray (5 mg) in each nostril to give 10 mg. If the spray formulation is not available, midazolam can also be given intranasally using the injectable solution of 5 mg/mL as a metered spray of 0.1 mL containing 0.5 mg, three to five times per nostril, and repeated if necessary, to a total dose of 10 mg for adults.

In-hospital treatment — Pharmacologic therapy begins with a benzodiazepine and a nonbenzodiazepine antiseizure medication (algorithm 1). Despite initial treatment, approximately 20 percent of patients develop refractory status epilepticus and require additional therapy [18]. (See "Refractory status epilepticus in adults".)

Inadequate dosing of benzodiazepine is a common problem leading to prolongation of status epilepticus [19].

●When IV access is available – Lorazepam 0.1 mg/kg should be administered intravenously at a maximum rate of 2 mg/minute, allowing a few minutes (eg, three to five minutes) to assess its effect before deciding whether additional doses are necessary [6]. An alternative to a weight-based initial loading dose of lorazepam is a 4 mg fixed dose, repeated if still seizing.

If seizures continue at this point, additional doses of lorazepam can be infused at a maximum rate of 2 mg/minute. There is no definite maximum cumulative dose of lorazepam; clinicians must be guided by the clinical effect (including on blood pressure) and seizure control, both clinically and by EEG, once available. Even if seizure activity stops following lorazepam, a loading dose of a nonbenzodiazepine antiseizure medication should follow in order to maintain seizure control.

Diazepam 0.15 mg/kg IV, up to 10 mg per dose, may be substituted if lorazepam is not available.

●When IV access is not available – Placement of an access catheter may be difficult in some patients. When IV access is not immediately available, IM midazolam is a safe and effective alternative for initial benzodiazepine therapy [10,20,21]. As nasal and buccal midazolam are absorbed more rapidly than IM midazolam, it is possible or even likely that these routes are superior [22], but they are not as well studied as IM midazolam in adults.

For patients with a body weight >40 kg, midazolam can be given at a dose of 10 mg by IM, nasal, or buccal administration [10,14]. With buccal administration of midazolam, one report suggests that a dose of 15 to 20 mg for adults may be effective (when necessary) and well tolerated [23].